DE102018112236B3 - Operating state-dependent fully automatic determination of the current measuring point in half bridges and full bridges by current sign detection - Google Patents

Abstract

The invention relates to a half-bridge device with the possibility of current measurement at its output (X). It has a terminal (X), a supply voltage (VSPX), a reference potential (GND), a half-bridge (T, T) with a high-side switch (T) and a low-side switch (T), a half-bridge control (1) with a set signal (SET) as an input signal, a current sign detecting device (2,3,4,5,6,7), a high-side measuring device (T ', T, V, S, S) and a Low-side measuring device (T ', T, V, S, S) on. The high-side switch (T) is connected between the connection (X) and the supply voltage (VSPX). The low-side switch (T) is connected between the terminal (X) and the reference potential (GND). The half-bridge controller (1) controls the half-bridge (T, T) of low-side switch (T) and high-side switch (T) in response to the set signal (SET). The high-side measuring device (T ', T, V, S, S) is used at least temporarily to detect the high-side switch current (I) through the high-side switch (T) and the low-side measuring device ( T ', T, V, S, S) at least temporarily detecting the low-side switch current (I) by the low-side switch (T). The current sign detecting device (2, 3, 4, 5, 6, 7) at least temporarily detects the sign of a residual bridge load current (I) in the terminal (X) of the half-bridge (T, T) and determines current direction information or generates a current direction signal ( CURRDIR). In the half-bridge device, the use or provision of either a value of the high-side switch current (1) detected by the high-side measuring device (T ', T, V, S, S) is effected by the high-side switch (T). or a value of the low-side switch current (I) detected by the low-side measuring device (T ', T, V, S, S) by the low-side switch (T) as the current measurement value of its current measurement at its output (X) depending on this current direction information or on the value of the current direction signal (CURRDIR).

Description

preamble

The invention is directed to an apparatus and a method for driving inductors by means of half-bridges. Here, the problem of operating state-dependent determination of the current measuring point in half bridges and full bridges is solved by current sign detection.

General introduction and prior art

There are in the prior art a variety of current measuring methods for measuring currents at inductances, which are based on measuring resistors, which are connected in series with the respective inductance and in which the voltage drop across these measuring resistors is detected. Such measuring resistors are also referred to below as shunt resistors. Furthermore, the measurement of currents by means of transistor current mirrors is known from the prior art. However, if the current is measured by means of a mirror method using current mirrors, it can only be reliably measured in one direction.

The prior art is based on the 1 and 2 explained.

First to 1 : Inductors ( L ) are controlled in many applications in the prior art with half-bridge circuits. A first half-bridge consists of a first high-side switch ( T _OH ), which in the closed state, the supply voltage ( VSPX ) with a first connection ( X ₀ ) of inductance ( L ) connects and in the open state, the supply voltage VSPX ) from this first connection ( X ₀ ) and a first low-side switch ( T _0L ), which has a reference potential ( GND ) with this first connection ( X ₀ ) of inductance ( L ) and in the opened state the reference potential ( GND ) from this first connection ( X ₀ ) separates. As a rule, the activation of the first high-side switch ( T _OH ) and the first low-side switch ( T _0L ) is controlled so that only ever the first high-side switch ( T _0H ) or the first low-side switch ( T _0L ) is closed, so that no cross-flow through the first half-bridge (T _OH , T _OL ) flows.

The first high-side switch ( T _0H ) is transmitted via a first control signal ( X _0H ) of the first high-side switch ( T _0H ) of the first half-bridge ( T _0H . T _0L ) controlled.

The first low-side switch ( T _0L ) is transmitted via a second control signal ( X _0L ) of the first low-side switch ( T _0L ) of the first half-bridge ( T _0H . T _0L ) controlled.

The second connection ( X ₁ ) of inductance ( L ) is either with a supply voltage potential, ie either the supply voltage ( VSPX ) or the reference potential ( GND ) or an intermediate potential (see 1 ) or with the output ( X ₁ ) a second half-bridge, ( T _1L . T _1H ) with a second high-side switch ( T _1H ) and a second low-side switch ( T _1L ) (please refer 2 ). Such a configuration of two half-bridges ( T _0L . T _0H . T _1L . T _1H ) is called in the following full bridge or H-bridge. The inductance ( L ) is between the two ports ( X ₁ . X ₂ ) of the two half bridges. Typically, the high-side switches ( T _0H . T _1H ) and the low-side switches ( T _0L . T _1L ) realized as transistors. With these half bridges ( T _0L . T _0H . T _1L . T _1H ) in the prior art, the voltage at the inductance ( L ) controlled. The resulting current through the inductance ( L ) is normally unknown and must be measured frequently. At best, this takes place directly via the switched-on transistor of the respective high-side switch ( T _0H . T _1H ) or the respective low-side switch ( T _0L . T _1L ). For this purpose, however, it is necessary that swelling currents (from the supply voltage ( VSPX ) in the inductance ( L ) on the high-side side and sinking currents (from the inductance ( L ) into the reference potential ( GND ) into) on the low-side side.

In the following, the current measurement at half bridges ( T _0L . T _0H . T _1L . T _1H ) for inductive loads in the form of inductors ( L ). In addition to the said current measurement via a shunt resistor in the current path of a half-bridge ( T _0L . T _0H . T _1L . T _1H ) is often used in integrated half-bridges ( T _0L . T _0H . T _1L . T _1H ) the current through the inductance ( L ) is measured by using a sense transistor, which is connected in parallel to the switching transistor in the respective half-bridge, a reference potential is generated, which is then used to control a measuring current source for a measuring current. This current mirror method has the advantage that no extra voltage drop and associated additional power loss is generated for measurement purposes.

The measuring principle is in 1 briefly presented.

In the first half bridge ( T _0L . T _OH ) the 1 is the output ( X ₀ ) of the first half-bridge ( T _0L . T _OH ) with a first terminal of the inductance ( L ) connected.

A first low-side amplifier ( V _0L ) compares the voltage drop across the first low-side switch ( T _0L ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across a first low-side sense transistor ( T ' _0L ). The first low-side measuring amplifier ( V _OL ) generates a first low-side control signal for the first low-side control transistor as a function of the voltage difference ( T _0RL ), this first low-side control signal for the first low-side control transistor ( T _ORL ) through this first low-side sense amplifier ( V _OL ) is preferably set so that the voltage drop across the first low-side switch ( T _0L ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across the first low-side sense transistor ( T ' _OL ) matches. The width of the first low-side sense transistor ( T ' _OL ) by one factor M _0L none is chosen as the width of the first low-side switch ( T _0L ). As a result, the first low-side sense current ( I ' _x0L ) by the first low-side switch ( T _0L ) by this factor M _0L smaller than the low-side switch current ( I _x0L ).

A first high-side measuring amplifier ( V _0H ) compares the voltage drop across the first high-side switch ( T _0H ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across a first high-side sense transistor ( T ' _0H ). The first high-side amplifier ( V _0H ) generates a first high-side control signal for the first high-side control transistor as a function of the voltage difference ( T _0RH ), this first high-side control signal for the first high-side control transistor ( T _0RH ) through this first high-side measuring amplifier ( V _0H ) is preferably set so that the voltage drop across the first high-side switch ( T _0H ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across the first high-side sense transistor ( T ' _0H ) matches. The width of the first high-side sense transistor ( T ' _0H ) by one factor M _0H no one is selected as the width of the first high-side switch ( T _0H ). This is the first high-side sense current ( I ' _x0H ) through the first high-side switch ( T _0H ) by this factor M _0H smaller than the high-side switch current ( I _x0H ).

A current mirror ( T _Mb . T _Ma ) reflects the low-side switch current ( I _x0L ) in the same direction as the high-side switch current ( I _x0H ). These currents can then be measured in further stages and used for control. As a rule, they are transformed into tensions for this purpose.

For half-bridges, the electrical current must be measured on the low-side and high-side. The from the half bridge ( T _0L . T _0H ) in the inductance ( L ) is on the high side ( T _0H . T ' _0H ) and the inductance ( L ) in the half bridge ( T _0L . T _0H ) is on the low side ( T _0L . T ' _0L ) measurable. A higher-level controller must select the measured value of the stage (high-side or low-side), which can just deliver a reliable measured value for the given current direction. Ie. in this case, the control needs information about the direction of the current in the output ( X ₀ ) of this half bridge in or out.

In a full bridge ( T _0L . T _0H . T _1L . T _1H ) (please refer 2 ), the current on the low-side side is always measured in the half-bridge into which the current flows. In the opposite direction, it is possible that a part of the current flows through the substrate diode of the turned-on transistor and falsifies the measurement result. With the selection signal ( MEAS1x ) selects the page with which the current can be measured correctly, or on which the current is sunk in this case. The offset signals (OFFSx0 [3: 0], OFFSx1 [3: 0]) set the offset of the first low-side amplifier ( V _OL ) and the second low-side measuring amplifier ( V _1L ) and are exemplified here as four-bit data buses. The principle could also be used alternatively on the high side. For simplicity, only the application to the low side will be discussed here. The difficulty now is the selection signal ( MEAS1x ) so that the condition of the correct current direction is satisfied. For this purpose, a reliable statement about the current direction is required, with the arrangement of the 2 can not be won.

From the prior art is with the DE 10 2015 118 210 A1 a current tracking system is known in which the strum is detected by a half-bridge. From the DE 10 2016 206 590 A1 is an H-bridge with detection of the current through the half-bridges known.

The o.g. Problems therefore lead to the need to develop a method to reliably detect the current direction in the respective half-bridge in or out of this and then to use the current measurement method correctly.

Object of the invention

The present arrangement makes it possible to detect the current direction in a push-pull driver stage and thus to identify the correct current measuring point in a half bridge or a full bridge. The invention is thus based on the object to provide a solution which does not have the above disadvantages of the prior art and has further advantages.

This object is achieved by devices according to claims 2 and 4 as well as by methods according to the claims 6 and 7 solved.

solution

Basically, one can say statements about the current direction at the output ( X ₀ ) of a half bridge ( T _0L . T _0H ) or at the two outputs ( X ₀ . X ₁ ) of a full bridge ( T _0L . T _0H . T _1L . T _1H ) when the voltage across the inductance ( L ) is known. With changing voltages, however, this must be observed over a longer period of time and the occurrence of induced voltages must also be taken into account. This estimation method for the current direction is thus unreliable, faulty and not stateless. Ie. after a reset of the device, the observation base must first be recreated.

It is now proposed to solve these problems during the switching operation of a half-bridge ( T _0L . T _0H ) the delay time between the switching signal ( X _0H . X _0L ) and the one at the exit ( X ₀ ) of the first half-bridge ( T _0H . T _0L ) to measure existing edge. This time is compared with a reference value ( V _ref ) and from this the decision for the probable current direction at the output ( X ₀ ) of the first half-bridge ( T _0H . T _0L ) won.

In a dead-time half-bridge circuit like the first half-bridge ( T _0H . T _0L ), the current direction is thus detected by the time between the triggering of the switching operation by a set signal ( SET ) (please refer 3 ) and the actual switching of the low-side switch ( T _0L ) and the high-side switch ( T _0H ) by detecting the resulting voltage jump of the first output voltage ( V _{0 PHASE} ) between the output ( X ₀ ) of the first half-bridge ( T _0H . T _0L ) and the reference potential ( GND ) is measured. For this purpose, the first output voltage ( V _{0 PHASE} ) by means of a first low-side comparator ( 3 ) with a first low-side threshold ( V _ref ) and by means of a first high-side comparator ( 2 ) with a first high-side threshold ( V _s -V _ref ) compared. becomes. Depending on the switching direction, the measured delay time is above the threshold value for a source current and below a threshold value for a sink current. delay source current sink current Switching process L-> H (rising edge at X ₀ Delay <Delay1a Delay> Delay timer1a Switching operation H-> L (falling edge at X ₀ Delay> Delay Hold1b Delay <Delay1b

For this purpose, a delay counter ( 4 ) the time between an edge of the set signal ( SET ), which has a rising edge at the output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ) and the appearance of the corresponding rising edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ). The measurement is preferably done by counting one here marked, very fast system base clock (CLK). The measurement in the form of counting by the delay counter ( 4 ) preferably begins with the edge on the set signal ( SET ) typically at the count 0 and typically ends with the corresponding edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ). The so by the delay counter ( 4 ) is determined by a first memory ( 5 ) for storing by the delay counter ( 4 ) for the detected delay from the edge of the set signal ( SET ) to the rising edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ) then as a valid LOW-HIGH delay value ( VDSH ) until successful completion of the next measurement. The delay counter ( 4 ) then gives the typically LOW HIGH delay value thus measured ( VDSH ) out.

Likewise, the delay counter ( 4 ) the time between a falling edge of the set signal ( SET ) and the appearance of the corresponding now but opposite edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ). The measurement is again preferably carried out by counting a very fast system basic clock (CLK), not shown here. The measurement in the form of counting by the delay counter ( 4 ) begins again preferably with the edge on the set signal ( SET ) typically at the count 0 and typically ends with the corresponding edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ). The so by the delay counter ( 4 ) is counted by another first memory ( 6 ) for storing by the delay counter ( 4 ) for the detected delay from the edge of the set signal ( SET ) to the falling edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ) then as a valid HIGH-LOW delay value ( VDSL ) until successful completion of the next measurement. The delay counter ( 4 ) then gives the typically the last HIGH-LOW delay value ( VDSL ) out.

In order to compensate for circuit-related influences resulting from the circuit-related delay times, the delays thus determined ( VDSH ) on the rising edge of the set signal ( SET ) and the delay ( VDSL ) on the falling edge of the set signal ( SET ) subtracted from each other. The difference value is then compared in a comparison stage ( 7 ) against a further delay statement ( DELTHR ) compared. The further delay derivative ( DELTHR ) would be in a fully symmetrical structure half bridges ( T _0H . T _0L ) are at zero.

The further delay derivative ( DELTHR ) results from the circuitry conditions and can be initially determined and stored. However, it can also be calibrated during operation by determining and storing the delay values at times of a safely known current direction. The distance between the delay values of different current direction depends on the set dead time. Thus, the signal to noise ratio for the decision making on the dead time is adjustable.

The solution underlying the solution consists of a half-bridge control ( 1 ) with adjustable dead time, one or more phase voltage comparators, here with a first high side comparator ( 2 ) and a first low-side comparator ( 2 ), a counting circuit for measuring the switching delays, here the one delay counter ( 4 ). Moreover, the underlying arrangement proposed herein comprises a first memory ( 5 ) for storing by the delay counter ( 4 ) for the detected delay from the edge of the set signal ( SET ) to the rising edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ) and another first memory ( 6 ) for storing by the delay counter ( 4 ) for the detected delay from the edge of the set signal ( SET ) to the falling edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ). Finally, the arrangement comprises a comparison stage ( 7 ) as a decision maker from which a current direction signal ( CURDIR ) generated. (Please refer 3 )

Depending on this current direction signal ( CURDIR ) is now within the device and / or by the comparison stage ( 7 ) the selection signal ( MEAS1x ), which is used as the source of the measured current value in the 2 between the first half bridge ( T _0L . T _0HH ) and the second half-bridge ( T _1L . T _1H ) switches. Also, within the device and / or by the comparison stage ( 7 ) in response to this current direction signal ( CURDIR ) the switches ( S _0GND . S ₀ . S _1GND . S ₁ ) converted.

Should the current measurement in the full bridge of the 2 in the first half-bridge ( T _0L . T _0H ), which is the case when the inductance ( L ) Current from the second half-bridge ( T _1L . T _1H ) and in the first port ( X ₀ ) feeds the first half-bridge, it is due to the logical value of the current direction signal ( CURDIR ) the first switch ( S ₀ ) and the second switch ( S _0GND ) and the third switch ( S ₁ ) and the fourth switch ( S _1GND ) closed. In that case, the second low-side control transistor ( T _1RL ) blocked. Thus, the second low-side sense current ( I ' _x1L ) to zero and the measuring current ( I _MEASx ) is in the 2 only by the first low-side switch current ( I _x0L ) certainly.

Should the current measurement in the full bridge of the 2 in the second half bridge ( T _1L . T _1H ), which is the case when the inductance ( L ) Current from the first half-bridge ( T _0L . T _0H ) and into the second port ( X ₁ ) of the second half-bridge ( T _1L . T _1H ), it is due to the logical value of the current direction signal ( CURDIR ) the first switch ( S ₀ ) and the second switch ( S _0GND ) and the third switch ( S ₁ ) and the fourth switch ( S _1GND ) open. In that case, the first low-side control transistor ( T _0RL ) blocked. This is the first low-side sense current ( I ' _xOL ) to zero and the measuring current ( I _MEASx ) is in the 2 only by the second low-side switch current ( I _X1L ) certainly.

Should the current measurement in the half bridge of the 1 in the high-side part ( T _0H ) of the first half-bridge ( T _0L . T _0H ), which is the case when the inductance ( L ) Current from the first half-bridge ( T _1L . T _1H ) at the first connection ( X ₀ ), it is due to the logical value of the current direction signal ( CURDIR ) the fifth switch ( S _XH ) and the sixth switch ( S _XHCL ) and the seventh switch ( S _XL ) and the fourth switch ( S _XLCL ) open. In that case, the first low-side control transistor ( T _0RL ), while the first high-side control transistor ( T _ORH ) is corrected. This is the first low-side sense current ( I ' _x1L ) to zero and the low-side measuring current ( I _MEASXL ) becomes zero. The high-side measuring current ( I _MEASxH ) is then in the 1 only by the first high-side switch current ( I _X0H ) certainly.

Should the current measurement in the half bridge of the 1 in the low-side part ( T _0L ) of the first half-bridge ( T _0L . T _0H ), which is the case when the inductance ( L ) Current in the first half-bridge ( T _1L . T _1H ) at the first connection ( X ₀ ), it is due to the logical value of the current direction signal ( CURDIR ) the fifth switch ( S _XH ) and the sixth switch ( S _XHCL ) and the seventh switch ( S _XL ) and the fourth switch ( S _XLCL ) closed. In that case, the first high-side control transistor ( T _0RH ), while the first low-side control transistor ( T _ORL ) is corrected. This is the first high-side sense current ( I ' _x1H ) to zero and the high-side measuring current ( I _MEASxH ) becomes zero. The low-side measuring current ( I _MEASXL ) is then in the 1 only by the first low-side switch current ( I _x0L ) certainly.

The control signals for the switches preferably generates the comparison stage ( 7 ) together with the current direction signal ( CURDIR ). It is also conceivable that the control signals for the switches in a separate stage from the current direction signal ( CURDIR ) to create.

It is also conceivable that 1 and 2 to combine with each other. This can be done, for example, by doubling the controls ( 3 ) happen.

Variant A) Half-bridge with switching between high-side measurement and low-side measurement as a function of the current sign

Thus, in the first place, a half-bridge device with the possibility of current measurement at its output ( X ₀ ), which provides a connection ( _XO ), a supply voltage ( VSPX ), a reference potential ( GND ), a half-bridge ( T _0H . T _0L ) with a high-side switch ( T _0H ) and a low-side switch ( T _0L ), a half-bridge controller ( 1 ), a set signal ( SET ), a current sign detecting device (2,3,4,5,6,7), a high-side measuring device ( _T'OH . T _ORH . V _OH . S _XH . S _XHCL ) and a low-side measuring device ( T ' _OL . T _ORL . V _OL . S _XL . S _XLCL ) having. The high-side switch ( T _0H ) is between the connector ( X ₀ ) and the supply voltage ( VSPX ). The low-side switch ( T _0L ) is between the connector ( X ₀ ) and the reference potential ( GND ). The set signal ( SET ) is an input signal of the half-bridge controller ( 1 ). The half-bridge control ( 1 ) controls the half-bridge ( T _0L . T _OH ) off low-side switch ( T _0L ) and high-side switches ( T _0H ) in response to the set signal ( SET ). The high-side measuring device ( _T'OH . T _ORH . V _OH . S _XH . S _XHCL ) serves at least temporarily the detection of the high-side switch current ( I _{x OH} ) through the high-side switch ( T _OH ). The low-side measuring device ( T ' _OL . T _ORL . V _OL . S _XL . S _XLCL ) serves at least temporarily the detection of the low-side switch current ( I _xOL ) through the low-side switch ( T _0H ). The current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ) serves at least temporarily to detect the sign of a Habbrückenlaststroms ( I _X0 ) in the connection ( X ₀ ) of the half bridge ( T _0L . T _0H ) and detects a current direction information or generates a current direction signal (CURRDIR). In the half-bridge device, depending on this current direction information or the value of the current direction signal (CURRDIR), either a signal passing through the high-side measuring device ( _T'OH . T _0RH . V _0H . S _XH . S _XHCL ) detected value of the high-side switch current ( I _x0H ) through the high-side switch ( T _0H ) or one through which the low-side measuring device ( T ' _0L . T _0RL . V _0L . S _XL . S _XLCL ) detected value of the low-side switch current ( I _x0L ) through the low-side switch ( T _0H ) as current reading of its current measurement at its output ( X ₀ ) used. Also, instead of or in addition, depending on this current direction information or the value of the current direction signal (CURRDIR), either a signal passing through the high-side measuring device ( T ' _0H . T _0RH . V _0H . S _XH . S _XHCL ) detected value of the high-side switch current ( I _x0H ) through the high-side switch ( T _0H ) or one through which the low-side measuring device ( T ' _0L . T _0RL . V _0L . S _XL . S _XLCL ) detected value of the low-side switch current ( I _x0L ) through the low-side switch ( T _0H ) as current reading of its current measurement at its output ( X ₀ ) for external uses.

A suitable current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ) for a half-bridge device for this purpose comprises, for example, a high-side comparator ( 2 ), a low-side comparator ( 3 ), with a delay counter ( 4 ), a memory ( 5 ), another memory ( 6 ) and a comparison stage ( 7 ). The high-side comparator ( 2 ) compares the potential at the output ( X ₀ ), on the one hand, with another reference value ( V _s -V _ref On the other hand, and depending on the result of this comparison, it generates a LOW-HIGH delay value (FIG. VDSH ). This can be done in particular by subtraction happen. The low-side comparator ( 3 ) compares the potential at the output ( X ₀ ), on the one hand, with a reference value ( V _ref or low-side threshold, on the other hand, and generates a HIGH-LOW delay value ( VDSL ). This too can be done by subtraction. The delay counter ( 4 ) detects the time between an edge of the set signal ( SET ) and the corresponding edge at the output ( X ₀ ) of the half bridge ( T _0L . T _0H ). This is preferably done by counting a fast clock. Other solutions, but in particular analog solutions are conceivable. The memory ( 5 ) stores one by the delay counter ( 4 ) detected quantity, the time from the edge of the set signal ( SET ) to the rising edge at the output ( X ₀ ) of the half bridge ( T _0L . T _0H ), as storage value. The further memory ( 6 ) one by the delay counter ( 4 ) detected further magnitude, the time from the opposite edge of the set signal ( SET ) to the falling edge at the output ( X ₀ ) of the half bridge ( T _0L . T _0H ), as another memory value. The comparison level ( 7 ), in particular by subtraction, from the memory value in the memory ( 5 ) and the further memory value in the further memory ( 6 ) the current direction information. The comparison level ( 7 ) alternatively or additionally, in particular by subtraction, generates from the memory value in the memory ( 5 ) and the further memory value in the further memory ( 6 ) the current direction signal (CURRDIR).

Variant B) Full bridge with switching between low-side measurement in the first half-bridge and low-side measurement of the second half-bridge as a function of the current sign

Thus, here secondly, a full bridge device with the possibility of a load current measurement at its first output ( X ₀ ) and / or its second output ( X ₁ ), with a first connection ( X ₀ ), a second port ( X ₁ ), a supply voltage ( VSPX ), a reference potential ( GND ), a first half bridge ( T _0H . T _0L ) with a first high-side switch ( T _0H ) and with a first low-side switch ( T _0L ), a second half-bridge ( T _1H . T _1L ) with a second high-side switch ( T _1H ) and a second low-side switch ( T _1L ), a half-bridge control ( 1 ), a set signal ( SET ), a current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ), a first low-side measuring device ( T ' _OL . T _0RL . V _0L . S _0GND . S ₀ ) and a second low-side measuring device ( T ' _1L . T _1RL . V _1L . S _1GND . S ₁ ). The first high-side switch ( T _0H ) is between the first port ( X ₀ ) and the supply voltage ( VSPX ). The second high-side switch ( T _1H ) is between the second port ( X ₁ ) and the supply voltage ( VSPX ). The first low-side switch ( T _0L ) is between the first port ( X ₀ ) and the reference potential ( GND ). The second low-side switch ( T _1L ) is between the second port ( X ₁ ) and the reference potential ( GND ). The set signal ( SET ) is an input signal of the at least one half-bridge controller ( 1 ). The half-bridge control ( 1 ) controls the first half-bridge ( T _0L . T _0H ) from the first low-side switch ( T _0L ) and the first high-side switch ( T _0H ) in response to the set signal ( SET ). The half-bridge control ( 1 ) controls the second half-bridge ( T _1L . T _1H ) from second low-side switch ( T _1L ) and second high-side switch ( T _1H ) in response to the set signal ( SET ) preferably complementary. The first low-side measuring device ( T ' _0L . T _0RL . V _0L . S _0GND . S ₀ ) serves at least temporarily the detection of the first low-side switch current ( I _x0L ) by the first low-side switch ( T _0L ). The second low-side measuring device ( T ' _1L . T _1RL . V _1L . S _1GND . S ₁ ) serves at least temporarily the detection of the second low-side switch current ( I _x1L ) by the second low-side switch ( T _1L ). The current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ) serves at least temporarily to detect the sign of a first bridge load current ( I _X0 ) in the first connection ( X ₀ ) of the first half-bridge ( T _0L , T ₀ ) into it. The current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ) detects current direction information and / or generates a current direction signal (CURRDIR). In the full-bridge device, depending on this current direction information or the value of the current direction signal (CURRDIR), either a signal is passed through the first low-side measuring device ( T ' _OL . T _ORL . V _OL . S _OGND . S ₀ ) detected value of the first low-side switch current ( I _x0L ) by the first low-side switch ( T _0L ) or a through the second low-side measuring device ( T ' _1L . T _1RL . V _1L . S _1GND . S ₁ ) detected value of the second low-side switch current ( I _x1L ) by the second low-side switch ( T _1L ) as current reading of its current measurement at its output ( X ₀ ) used. Alternately or in parallel with this, either the full-bridge device is triggered by the first low-side measuring device as a function of this current direction information or the value of the current direction signal (CURRDIR). T ' _OL . T _ORL . V _OL . S _0GND . S _O ) detected value of the first low-side switch current ( I _x0 ) by the first low-side switch ( T _0L ) or a through the second low-side measuring device ( T ' _1L . T _1RL . V _1L . S _1GND . S ₁ ) detected value of the second low-side switch current ( I _x1L ) by the second low-side switch ( T _1L ) as current reading of its current measurement at its output ( X ₀ ).

A suitable exemplary current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ) for such a full-bridge device preferably comprises a high-side comparator ( 2 ), a low-side comparator ( 3 ), a delay counter ( 4 ), a memory ( 5 ), another memory ( 6 ) and a comparison stage ( 7 ). The high-side comparator ( 2 ) compares the potential at the output ( X ₀ ) of the first half-bridge ( T _0H . T _0L ) with another reference value ( V _s -V _ref ) or a high-side threshold value and generates a LOW-HIGH delay value as a function of the comparison result ( VDSH ). The low-side comparator ( 3 ) compares that Potential at the output (Xo) with a reference value ( V _ref ) or low-side threshold value and generates a HIGH-LOW delay value as a function of the comparison result ( VDSL ). The delay counter ( 4 ) detects the time between an edge of the set signal ( SET ) and the corresponding edge at the output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ). The memory ( 5 ) stores one by the delay counter ( 4 ) detected time from the edge of the set signal ( SET ) to the rising edge at the output ( X ₀ the first half bridge ( T _0L . T _0H ) as a memory value. The further memory ( 6 ) stores one by the delay counter ( 4 ) detected time from the opposite edge of the set signal ( SET ) to the falling edge at the output ( X ₀ the first half bridge ( T _0L . T _0H ) as another memory value. The comparison level ( 7 ) determined from the memory value in the memory ( 5 ) and the further memory value in the further memory ( 6 ) the current direction information and / or generated from the memory value in the memory ( 5 ) and the further memory value in the further memory ( 6 ) the current direction signal (CURRDIR).

Variant C) Full bridge with switching between high-side measurement in the first half-bridge and high-side measurement of the second half-bridge depending on the current sign

Third, here is a full bridge device with the possibility of a load current measurement at its first output ( X ₀ ) and / or its second output, which has a first connection ( X ₀ ), a second port ( X ₁ ), a supply voltage ( VSPX ), a reference potential ( GND ), a first half-bridge ( T _0H . T _0L ) with a first high-side switch ( T _0H ) and with a first low-side switch ( T _0L ), a second half-bridge ( T _1H . T _1L ) with a second high-side switch ( T _1H ) and a second low-side switch ( T _1L ), a half-bridge controller ( 1 ), a set signal ( SET ), a current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ), a first high-side measuring device ( T ' _0H . T _0RH . V _0H . S _0GND . S ₀ ) and a second high-side measuring device ( T ' _1H . T _1RH . V _1H . S _1GND . S ₁ ). The first high-side switch ( T _0H ) is again between the first connection (Xo) and the supply voltage ( VSPX ). The second high-side switch ( T _1H ) is between the second port ( X ₁ ) and the supply voltage ( VSPX ). The first low-side switch ( T _0L ) is between the first connection ( X ₀ ) and the reference potential ( GND ). The second low-side switch ( T _1L ) is between the second port ( X ₁ ) and the reference potential ( GND ). The set signal ( SET ) is an input signal of the at least one half-bridge controller ( 1 ). The half-bridge control ( 1 ) controls the first half-bridge ( T _0L . T _0H ) from the first low-side switch ( T _0L ) and the first high-side switch ( T _0H ) in response to the set signal ( SET ) and the second half-bridge ( T _1L . T _1H ) from second low-side switch ( T _1L ) and second high-side switch ( T _1H ) in response to the set signal ( SET ) complementary to it. The first high-side measuring device ( T ' _0H . T _0RH . V _0H . S _0GND . S ₀ ) is used at least temporarily the detection of the first high-side switch current ( I _x0H ) through the first high-side switch ( T _0H ). The second high-side measuring device ( T ' _1H . T _1RH . V _1H . S _1GND . S ₁ ) serves at least temporarily the detection of the second high-side switch current ( I _x1H ) through the second high-side switch ( T _1H ). The current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ) serves at least temporarily to detect the sign of a first bridge load current ( I _X0 ) in the first connection ( X ₀ ) of the first half-bridge ( T _0L . T _0H ) into it. Depending on the detected sign, the current sign detecting device ( 2 . 3 . 4 . 5 . 6 . 7 ), as elsewhere in this disclosure, provides direction information or generates a current direction signal (CURRDIR). In the full-bridge device, depending on this current direction information or the value of the current direction signal (CURRDIR), either a signal passing through the first high-side measuring device ( T ' _0H . T _0RH . V _0H . S _0GND . S ₀ ) detected value of the first high-side switch current ( I _{x OH} ) through the first high-side switch ( T _0H ) or through the second high-side measuring device ( T _1H . T _1RH . V _1H . S _1GND . S ₁ ) detected value of the second high-side switch current ( I _x1H ) through the second high-side switch ( T _1H ) is used as the current reading of its current measurement at its output (Xo).

Alternatively or in parallel, in the full-bridge device, depending on this current direction information or on the value of the current direction signal (CURRDIR), either a signal passing through the first high-side measuring device (FIG. T ' _0H . T _0RH . V _0H . S _0GND . S ₀ detected value of the first high-side switch current ( I _x0 ) through the first high-side switch ( T _0H ) or through the second high-side measuring device ( T ' _1H . T _1RH . V _1H . S _1GND . S ₁ ) detected value of the second high-side switch current ( I _x1H ) through the second high-side switch ( T _1H ) as current reading of its current measurement at its output ( X ₀ ).

A current sign detecting device suitable for this full bridge device ( 2 . 3 . 4 . 5 . 6 . 7 ) comprises a high-side comparator ( 2 ), a low-side comparator ( 3 ), a delay counter ( 4 ), a memory ( 5 ), another memory ( 6 ) and a comparison stage ( 7 ). The high-side comparator ( 2 ) compares the potential at the output ( X ₀ the first half bridge ( T _0H . T _0L ) with a further reference value ( V _s -V _ref ) or a high-side threshold and generates a LOW-HIGH delay value (depending on the result of this comparison ( VDSH ). The low-side comparator ( 3 ) compares the potential at the output ( X ₀ ) with a reference value ( V _ref ) or a low-side threshold and generates this depending on the result Compare a HIGH-LOW delay value ( VDSL ). The delay counter ( 4 ) detects a time value for the time between an edge of the set signal ( SET ) and the corresponding edge at the output ( X ₀ the first half bridge ( T _0L . T _0H ). The memory ( 5 ) stores one by the delay counter ( 4 ) detected time value for the time from the edge of the set signal ( SET ) to the rising edge at the output ( X ₀ ) of the first half-bridge ( T _0L . T _0H ) as a memory value. The further memory ( 6 ) stores one by the delay counter ( 4 ) detected further time value for the time of the opposite edge of the set signal ( SET ) to the falling edge at the output ( X ₀ the first half bridge ( T _0L . T _0H ) as another memory value. The comparison level ( 7 ) determined from the memory value in the memory ( 5 ) and the further memory value in the further memory ( 6 ) detects the current direction information and / or generates the current direction signal (CURRDIR).

Method for variant A) Half-bridge with switching between high-side measurement and low-side measurement as a function of the current sign

• • Bereitstellen eines Setz-Signals (SET) mit einer ersten Flanke;
• • Erzeugen einer fallenden Flanke am Ausgang (X₀ der Halbbrücke (T_0H , T_0L ) mit einer ersten Verzögerungszeit im zeitlichen Zusammenhang mit der ersten Flanke und erfassen dieser ersten Verzögerungszeit;
• • Erzeugen einer zweiten Flanke auf dem Setz-Signal (SET, die der ersten Flanke entgegengesetzt ist;
• • Erzeugen einer steigenden Flanke am Ausgang (X₀ der Halbbrücke (T_0H , T_0L ) mit einer zweiten Verzögerungszeit im zeitlichen Zusammenhang mit der zweiten Flanke und erfassen dieser zweiten Verzögerungszeit;
• • Bilden der Differenz zwischen der ersten erfassten Verzögerungszeit und der zweiten erfassten Verzögerungszeit;
• • Festlegung, ob der High-Side-Schalterstrom (I_x0 ) durch den High-Side-Schalter (T_0H ) oder der Low-Side-Schalterstrom (I_x0L ) durch den Low-Side-Schalter (T_0L ) als Repräsentant des Laststromes (IL) gemessen werden soll in Abhängigkeit von dieser Differenz;
• • Messung des so ausgewählten Schalterstroms (I_x0L , I_x0H ) als Repräsentanten des Laststromes (I_L) und Ausgabe oder Bereitstellung eines entsprechenden Laststrommesswerts.

Thus, a method has been described above for determining the load current (IL) in an inductive load ( L ) or from an inductive load ( L ), in which the inductive load ( L ) to the exit ( X ₀ ) of a half bridge ( T _0H . T _0L ) with a high-side switch ( T _0H ) and with a low-side switch ( T _0L ) connected. The method comprises, as proposed, the steps:

• Providing a set signal ( SET ) with a first edge;
• • generating a falling edge at the output ( X ₀ the half-bridge ( T _0H . T _0L ) having a first delay time in temporal relationship with the first edge and detecting this first delay time;
• Generating a second edge on the set signal ( SET which is opposite to the first edge;
• • generating a rising edge at the output ( X ₀ the half-bridge ( T _0H . T _0L ) having a second delay time in temporal relationship with the second edge and detecting this second delay time;
• • forming the difference between the first detected delay time and the second detected delay time;
• • Determining whether the high-side switch current ( I _x0 ) through the high-side switch ( T _0H ) or the low-side switch current ( I _x0L ) through the low-side switch ( T _0L ) is to be measured as a representative of the load current (IL) as a function of this difference;
• • Measurement of the selected switch current ( I _x0L . I _x0H ) representing the load current (I _L ) and outputting or providing a corresponding load current measurement value.

Method for variant B) full bridge with switching between low-side measurement in the first half-bridge and low-side measurement of the second half-bridge as a function of the current sign

• • Bereitstellen eines Setz-Signals (SET);
• • Erzeugen einer ersten Flanke auf dem Setz-Signal (SET);
• • Erzeugen einer fallenden Flanke am ersten Ausgang (X₀ der ersten Halbbrücke (T_0H , T_0L ) mit einer ersten Verzögerungszeit im zeitlichen Zusammenhang mit der ersten Flanke und erfassen dieser ersten Verzögerungszeit und Erzeugen einer steigenden Flanke am zweiten Ausgang (X₁ ) der zweiten Halbbrücke (T_1H , T_1L ) im zeitlichen Zusammenhang mit der ersten Flanke;
• • Erzeugen einer zweiten Flanke auf dem Setz-Signal (SET), die der ersten Flanke entgegengesetzt ist;
• • Erzeugen einer steigenden Flanke am ersten Ausgang (X₀ der ersten Halbbrücke (T_0H , T_0L ) mit einer zweiten Verzögerungszeit im zeitlichen Zusammenhang mit der zweiten Flanke und erfassen dieser zweiten Verzögerungszeit und Erzeugen einer fallenden Flanke am zweiten Ausgang (X₁ ) der zweiten Halbbrücke (T_1H , T_1L ) im zeitlichen Zusammenhang mit der zweiten Flanke;
• • Bilden der Differenz zwischen der ersten erfassten Verzögerungszeit und der zweiten erfassten Verzögerungszeit;
• • Festlegung, ob der erste Low-Side-Schalterstrom (I_x0L ) durch den ersten Low-Side-Schalter (T_0L ) oder der zweite Low-Side-Schalterstrom (I_x1L ) durch den zweiten Low-Side-Schalter (T_1L ) als Repräsentant des Laststromes (IL) gemessen werden soll in Abhängigkeit von dieser Differenz;
• • Messung des so ausgewählten Schalterstroms (I_x0L , I_x1L ) als Repräsentanten des Laststromes (II) und Ausgabe oder Bereitstellung eines entsprechenden Laststrommesswerts.

It was thus above a method for determining the load current ( I _L ) into an inductive load ( L ) or from an inductive load ( L ), in which the inductive load ( L ) between the first output ( X ₀ ) a first half-bridge ( T _0H . T _0L ) with a first high-side switch ( T _0H ) and with a first low-side switch ( T _0L ) and the second output ( X ₁ ) a second half-bridge ( T _1H . T _1L ) with a second high-side switch ( T _1H ) and with a second low-side switch ( T _1L ) is switched. The proposed method comprises the steps:

• Providing a set signal ( SET );
• • generating a first edge on the set signal ( SET );
• • generating a falling edge at the first output ( X ₀ the first half bridge ( T _0H . T _0L ) having a first delay time in temporal relationship with the first edge and detecting this first delay time and generating a rising edge at the second output ( X ₁ ) of the second half-bridge ( T _1H . T _1L ) in temporal relation to the first flank;
• Generating a second edge on the set signal ( SET ) which is opposite to the first edge;
• • generating a rising edge at the first output ( X ₀ the first half bridge ( T _0H . T _0L ) having a second delay time in temporal relationship with the second edge and detecting this second delay time and generating a falling edge at the second output ( X ₁ ) of the second half-bridge ( T _1H . T _1L ) in temporal relation to the second flank;
• • forming the difference between the first detected delay time and the second detected delay time;
• Determining whether the first low-side switch current ( I _x0L ) by the first low-side switch ( T _0L ) or the second low-side switch current ( I _x1L ) by the second low-side switch ( T _1L ) as a representative of the load current ( IL ) is to be measured as a function of this difference;
• • Measurement of the selected switch current ( I _x0L . I _x1L ) as representative of the load current (II) and output or provision of a corresponding load current measurement value.

Method for variant C) full bridge with switching between high-side measurement in the first half-bridge and high-side measurement of the second half-bridge as a function of the current sign

• • Bereitstellen eines Setz-Signals (SET);
• • Erzeugen einer ersten Flanke auf dem Setz-Signal (SET);
• • Erzeugen einer fallenden Flanke am ersten Ausgang (X₀ ) der ersten Halbbrücke (T_0H , T_0L ) mit einer ersten Verzögerungszeit im zeitlichen Zusammenhang mit der ersten Flanke und erfassen dieser ersten Verzögerungszeit und Erzeugen einer steigenden Flanke am zweiten Ausgang (X₁ ) der zweiten Halbbrücke (T_1H , T_1L ) im zeitlichen Zusammenhang mit der ersten Flanke;
• • Erzeugen einer zweiten Flanke auf dem Setz-Signal (SET), die der ersten Flanke entgegengesetzt ist;
• • Erzeugen einer steigenden Flanke am ersten Ausgang (X₀ der ersten Halbbrücke (T_0H , T_0L ) mit einer zweiten Verzögerungszeit im zeitlichen Zusammenhang mit der zweiten Flanke und erfassen dieser zweiten Verzögerungszeit und Erzeugen einer fallenden Flanke am zweiten Ausgang (X₁ ) der zweiten Halbbrücke (T_1H , T_1L ) im zeitlichen Zusammenhang mit der zweiten Flanke;
• • Bilden der Differenz zwischen der ersten erfassten Verzögerungszeit und der zweiten erfassten Verzögerungszeit;
• • Festlegung, ob der erste High-Side-Schalterstrom (I_x0L ) durch den ersten High-Side-Schalter (T_0H ) oder der zweite High-Side-Schalterstrom (I_x1H ) durch den zweiten High-Side-Schalter (T_1H ) als Repräsentant des Laststromes (I_L ) gemessen werden soll in Abhängigkeit von dieser Differenz;
• • Messung des so ausgewählten Schalterstroms (I_x0H , I_x1H ) als Repräsentanten des Laststromes (I_L) und Ausgabe oder Bereitstellung eines entsprechenden Laststrommesswerts.

It was thus above a method for determining the load current ( IL ) into an inductive load ( L ) or from an inductive load ( L ), in which the inductive load ( L ) between the first output ( X ₀ a first half-bridge ( T _0H . T _0L ) with a first high-side switch ( T _0H ) and with a first low-side switch ( T _0L ) and the second output ( X ₁ ) a second half-bridge ( T _1H . T _1L ) with a second high-side switch ( T _1H ) and with a second low-side switch ( T _1L ) is switched. The method comprises the steps

• Providing a set signal ( SET );
• • generating a first edge on the set signal ( SET );
• • generating a falling edge at the first output ( X ₀ ) of the first half-bridge ( T _0H . T _0L ) having a first delay time in temporal relationship with the first edge and detecting this first delay time and generating a rising edge at the second output ( X ₁ ) of the second half-bridge ( T _1H . T _1L ) in temporal relation to the first flank;
• Generating a second edge on the set signal ( SET ) which is opposite to the first edge;
• • generating a rising edge at the first output ( X ₀ the first half bridge ( T _0H . T _0L ) having a second delay time in temporal relationship with the second edge and detecting this second delay time and generating a falling edge at the second output ( X ₁ ) of the second half-bridge ( T _1H . T _1L ) in temporal relation to the second flank;
• • forming the difference between the first detected delay time and the second detected delay time;
• • Determining whether the first high-side switch current ( I _x0L ) through the first high-side switch ( T _0H ) or the second high-side switch current ( I _x1H ) through the second high-side switch ( T _1H ) as a representative of the load current ( I _L ) is to be measured as a function of this difference;
• • Measurement of the selected switch current ( I _x0H . I _x1H ) representing the load current (I _L ) and outputting or providing a corresponding load current measurement value.

advantages

The current direction can be safely detected because the circuit used is much more robust to substrate currents than a parallel current measuring circuit. This allows the reliable measurement of the current with a mirror process.

LIST OF REFERENCE NUMBERS

1

Half bridge control;

2

first high-side comparator;

3

first low-side comparator;

4

Delay counter;

5

first memory for the detected delay from the edge of the set signal ( SET ) to the rising edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H );

6

further first memory for the detected delay from the edge of the set signal ( SET ) to the falling edge at the first output ( X ₀ ) of the first half-bridge ( T _0L . T _0H );

7

Comparator;

CURDIR

Current direction signal;

DELTHR

Delay derivative;

GND

Reference potential;

I _MEASx

Measuring current;

I _x0

first Habbrückenlaststrom in the first port ( X ₀ ) of the first half-bridge ( T _0L . T _0H into it .;

I ' _x0L

first low-side sense current;

I _x0L

first low-side switch current;

I ' _x0H

first high-side sense current;

I _x0H

first high-side switch current;

I ' _x1L

second low-side sense current;

I _x1L

second low-side switch current;

I ' _XIH

second high-side sense current;

I _XIH

second high-side switch current;

L

Inductance associated with the first half-bridge ( T _0L . T _0H ) or the full bridge ( T _0L . T _0H . T _1L . T _1H ) from the first half-bridge ( T _0L . T _0H ) and the second half bridge ( T _1L . T _1H ) is to be controlled;

MEAS1x

Selection signal. With the selection signal, the page is selected with which the current can be measured correctly, or on which the current is sunk in this case;

SET

Set signal.

T _0H

first high-side switch (transistor) of the first half-bridge ( T _0H . T _0L );

T ' _0H

first high-side sense transistor of the first half-bridge ( T _0H . T _0L );

T _0L

first low-side switch (transistor) of the first half-bridge ( T _0H . T _0L );

T ' _0L

first low-side sense transistor of the first half-bridge ( T _0H . T _0L );

T _0RH

first high-side control transistor;

T _0RL

first low-side control transistor;

T _1H

second high-side switch (transistor) of the second half-bridge ( T _1H . T _1L );

T ' _1H

second high-side sense transistor of the second half-bridge ( T _1H . T _1L );

T _1L

second low-side switch (transistor) of the second half-bridge ( T _1H . T _1L );

T ' _1L

second low-side sense transistor of the second half-bridge ( T _1H . T _1L );

T _1RH

second high-side control transistor;

T _1RL

second low-side control transistor;

V _0L

first low-side measuring amplifier for comparing the voltage drop across the first low-side transistor ( T _0L ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across the first low-side sense transistor ( T ' _0L ) and for generating a first control signal for the first low-side control transistor ( T _0RL ), this first control signal for the first low-side control transistor ( T _0RL ) is preferably set by this first low-side measuring amplifier such that the voltage drop across the first low-side transistor ( T _0L ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across the first low-side sense transistor ( T ' _0L) matches;

V _0H

first high-side measuring amplifier for comparing the voltage drop across the first high-side transistor ( T _0H ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across the first high-side sense transistor ( T ' _0H ) and for generating a first control signal for the first high-side control transistor ( T _0RH ), this first control signal for the first high-side control transistor ( T _0RH ) is preferably set by this first high-side measuring amplifier such that the voltage drop across the first high-side transistor ( T _0H ) of the first half-bridge ( T _0H . T _0L ) with the voltage drop across the first high-side sense transistor ( T ' _0H ) matches;

V _1L

second low-side measuring amplifier for comparing the voltage drop across the second low-side transistor ( T _0H ) of the second half-bridge ( T _1H . T _1L ) with the voltage drop across the second low-side sense transistor ( T ' _1L ) and for generating a second control signal for the second low-side control transistor ( T _1RHL ), this second control signal for the second low-side control transistor ( T _1RL ) is preferably set by this second low-side measuring amplifier such that the voltage drop across the second low-side transistor ( T _1L ) of the second half-bridge ( T _1H . T _1L ) with the voltage drop across the second low-side sense transistor ( T ' _1L) matches;

V _1H

second high-side measuring amplifier for comparing the voltage drop across the second high-side transistor ( T _1H ) of the second half-bridge ( T _1H . T _1L ) with the voltage drop across the second high-side sensing transistor ( T ' _1H ) and for generating a second control signal for the second high-side control transistor ( T _1RH ), this second control signal for the second high-side control transistor ( T _1RH ) is preferably set by this second high-side measuring amplifier such that the voltage drop across the second high-side transistor ( T _1H ) of the second half-bridge ( T _1H . T _1L ) with the voltage drop across the second high-side sensing transistor ( T ' _1H ) matches;

V _{0 PHASE}

first output voltage between the first output ( X ₀ ) of the first half-bridge ( T _0H . T _0L ) and the reference potential ( GND );

V _{1 PHASE}

second output voltage between the second output ( X ₁ ) of the second half-bridge ( T _1H . T _1L ) and the reference potential ( GND );

VDSH

through the delay counter ( 4 ) determined LOW-HIGH delay value;

VDSL

through the delay counter ( 4 ) determined HIGH-LOW delay value;

V _ref

Reference value or low-side threshold;

VSPX

Supply voltage of the first half-bridge ( T _0L . T _0H ) or full bridge ( T _0L . T _0H . T _1L . T _1H ):

V _s -V _ref

another reference value or high-side threshold;

X ₀

first connection of the inductance ( L );

X _0H

first control signal of the first high-side switch ( T _0H ) of the first half-bridge ( T _0H . T _0L );

X _0L

second control signal of the first low-side switch ( T _0L ) of the first half-bridge ( T _0H . T _0L );

X ₁

second connection of the inductance ( L );

X _1H

third control signal of the second high-side switch ( T _1H ) of the second half-bridge ( T _1H , T _1L );

X _1L

fourth control signal of the second low-side switch ( T _1L ) of the second half-bridge ( T _1H . T _1L );

Claims (7)

Current sign detecting device (2,3,4,5,6,7) for a half-bridge device - with a high-side comparator (2) and - with a low-side comparator (3) and - with a delay counter (4) and - with a memory (5) and - with a further memory (6) and - with a comparison stage (7), - wherein the high-side comparator (2) the potential at the output (X ₀ ) with a further reference value (V _s -V _ref ) or high-side threshold value and generates a LOW-HIGH delay value (VDSH) and - wherein the low-side comparator (3) the potential at the output (X ₀ ) with a reference value (V _ref ) or Low-side threshold compares and generates a HIGH-LOW delay value (VDSL) and wherein the delay counter (4) detects the time between an edge of the set signal (SET) and the corresponding edge at the output (X ₀ ) of the half-bridge (T _0L , T _0H ) and - wherein the memory (5) by the delay _counter (4 ) detected time from the edge of the set signal (SET) to the rising edge at the output (X ₀ ) of the half-bridge (T _0L , T _0H ) stores as memory _value and - the further memory (6) by the delay counter (4) detected time from the opposite edge of the set signal (SET) to the falling edge at the output (X ₀ ) of the half-bridge (T _0L , T _0H ) stores as a further memory value and - wherein the comparison stage (7) from the memory value in the memory (5 ) and the further memory value in the further memory (6) determines the current direction information or generates the current direction signal (CURRDIR) and - wherein the half-bridge device provides the possibility of a current measurement at its output (X ₀ ) and - wherein the Halbbrü • with a connection (X ₀ ) and • with a supply voltage (VSPX) and • with a reference potential (GND) and • with a half-bridge (T _0H , T _0L ) ■ with a high-side switch (T _0H ) and ■ with a low-side switch (T _0L ) and • with a half-bridge control (1) and • with a set signal (SET) • with a current sign detection device (2,3,4,5,6,7) and, • with a high-side measuring device (T ' _0H , T _0RH , V _0H , S _XH , S _XHCL ) and • with a low-side measuring device (T' _0L , T _0RL , V _0L , S _XL , S _XLCL ) , is provided and - wherein the high-side switch (T _0H ) between the terminal (X ₀ ) and the supply voltage (VSPX) is connected and - wherein the low-side switch (T _0L ) between the terminal (X ₀ ) and the reference potential (GND) is connected and - wherein the set signal (SET) is an input signal of the half-bridge controller (1) and - wherein the half-bridge _controller (1) the half-bridge (T _0L , T _0H ) from Low-Sid e-switch (T _0L ) and high-side switch (T _0H ) in response to the set signal (SET) controls and - wherein the high-side measuring device (T ' _0H , T _0RH , V _0H , S _XH , S _XHCL ) at least temporarily _{serves to} detect the high-side switch _current (I _x0H ) by the high-side switch (T _0H ), and - wherein the low-side measuring device (T ' _0L , T _0RL , V _0L , S _XL , S _XLCL ) _serves, at least at times, to detect the low-side switch _current (I _x0L ) through the low-side switch (T _0H ), and - the current sign detecting device (2, 3, 4, 5, 6, 7) ) at least temporarily for detecting the sign of a Habbrückenlaststroms (I _x0 ) in the terminal (X ₀ ) of the half-bridge (T _0L , T _0H ) inside and determines a current direction information or generates a current direction signal (CURRDIR) and - wherein in the half-bridge device in dependence from this current direction information or the value of the current direction signal (CURRDIR) either one through the high-side measuring device tion (T ' _0H , T _0RH , V _0H , S _XH , S _XHCL ) detected value of the high-side switch _current (I _x0H ) by the high-side switch (T _0H ) or one of the low-side _Measuring device (T ' _0L , T _0RL , V _0L , S _XL , S _XLCL ) detected value of the low-side switch _current (I _x0L ) through the low-side switch (T _0H ) as the current reading of their current measurement at its output (X ₀ ) uses or provides. Full bridge device with the possibility of a load current measurement at its first output (X ₀ ) and / or its second output - with a first terminal (X ₀ ) and - with a second terminal (X ₁ ) and - with a supply voltage (VSPX) and - with a reference potential (GND) and - with a first half-bridge (T _0H , T _0L ) • with a first high-side switch (T _0H ) and • with a first low-side switch (T _0L ) and - with a second one Half-bridge (T _1H , T _1L ) • with a second high-side switch (T _1H ) and • with a second low-side switch (T _1L ) and - with a half-bridge control (1) and - with a set signal (SET) - with a current sign detecting device (2,3,4,5,6,7) and, - with a first low-side measuring device (T ' _0L , T _0RL , V _0L , S _0GND , S ₀ ) and - with a second low-side measuring device (T ' _1L , T _1RL , V _1L , S _1GND , S ₁ ) and - wherein the first high-side switch (T _0H ) between the first terminal (X ₀ ) and the supply voltage (VSPX) is connected and - wherein the second high-side switch (T _1H ) between the second terminal (X ₁ ) and the supply voltage (VSPX) is connected and - wherein the first low-side switch (T _0L ) between the first terminal (X ₀ ) and the reference potential (GND) is connected and - wherein the second low-side switch (T _1L ) between the second terminal (X ₁ ) and the reference potential (GND) is connected and - wherein the Setz Signal (SET) is an input signal of the at least one half-bridge controller (1), and - wherein the half-bridge _controller (1) _comprises the first half-bridge (T _0L , T _0H ) from the first low-side switch (T _0L ) and the first high-side Switch (T _0H ) in response to the set signal (SET) controls and - wherein the half-bridge controller (1) the second half-bridge (T _1L , T _1H ) from second low-side switch (T _1L ) and second high-side switch (T _1H ) in response to the set signal (SET) complementary controls and - wherein the first low-side measuring device (T ' _0L , T _0RL , V _0L , S _0GND , S ₀ ) _serves at least temporarily to detect the first low-side switch _current (I _x0L ) by the first low-side switch (T _0L ) and, Side measuring device (T ' _1L , T _1RL , V _1L , S _1GND , S ₁ ) at least temporarily the detection of the second low-side switch _current (I _x1L ) by the second low-side switch (T _1L ) is used and, - wherein the current sign detecting device (2,3,4,5,6,7) at least temporarily for detecting the sign of a first Habbrückenlaststroms (I _x0 ) in the first terminal (X ₀ ) of the first half-bridge (T _0L , T _0H ) into it and a Stromrichtungsinformation determined or generates a current direction signal (CURRDIR) and - wherein in the full bridge device in response to this current direction information or the value of the current direction signal (CURRDIR) either by a first low-side measuring device (T ' _0L , T _0RL , V _0L , S _0GND , S ₀ ) detected value of the first low-side switch _current (I _x0L ) by the first low-side switch (T _0L ) or a _detected by the second low-side measuring device (T ' _1L , T _1RL , V _1L , S _1GND , S ₁ ) value of the second low-side switch _current (I _x1L ) is used or provided by the second low-side switch (T _1L ) as the current reading of its current measurement at its output (X ₀ ). Current sign detecting device (2,3,4,5,6,7) for a full bridge device according to claim 2 - with a high-side comparator (2) and - with a low-side comparator (3) and - with a delay counter (4 ) and - with a memory (5) and - with a further memory (6) and - with a comparison stage (7), - wherein the high-side comparator (2) the potential at the output (X ₀ ) of the first half-bridge ( T _0H , T _0L ) is compared with a further reference value (V _s -V _ref ) or high-side threshold value and generates a LOW-HIGH delay value (VDSH), and - wherein the low-side comparator (3) the potential at Compares output (X ₀ ) with a reference value (V _ref ) or low-side threshold value and generates a HIGH-LOW delay value (VDSL), and - wherein the delay counter (4) determines the time between an edge of the set signal (SET) and the corresponding edge at the output (X ₀ ) of the first half-bridge (T _0L , T _0H ) detected and - wherein the memory (5) by the Verz ogerungszähler (4) detected time from the edge of the set signal (SET) to the rising edge at the output (X ₀ ) of the first half-bridge (T _0L , T _0H ) stores as a memory _value and - wherein the further memory (6) one through the Delay counter (4) recorded time from the opposite edge of the set signal (SET) to the falling edge at the output (X ₀ ) of the first half-bridge (T _0L , T _0H ) as a further memory value stores and - Wherein the comparison stage (7) from the Memory value in the memory (5) and the further memory value in the further memory (6) determines the current direction information or generates the current direction signal (CURRDIR). Full bridge device with the possibility of a load current measurement at its first output (X ₀ ) and / or its second output - with a first terminal (X ₀ ) and - with a second terminal (X ₁ ) and - with a supply voltage (VSPX) and - with a reference potential (GND) and - with a first half-bridge (T _0H , T _0L ) • with a first high-side switch (T _0H ) and • with a first low-side switch (T _0L ) and - with a second half-bridge (T _1H , T _1L ) • with a second high-side switch (T _1H ) and • with a second low-side switch (T _1L ) and - with a half-bridge control (1) and - with one Set signal (SET) - with a current sign detecting device (2,3,4,5,6,7) and, - with a first high-side measuring device (T ' _0H , T _0RH , V _0H , S _0GND , S ₀ ) and - with a second high-side measuring device (T ' _1H , T _1RH , V _1H , S _1GND , S ₁ ) and - wherein the first high-side switch (T _0H ) between the first terminal (X ₀ ) and the supply voltage (VSPX) is connected and - wherein the second high-side switch (T _1H ) is connected between the second terminal (X ₁ ) and the supply voltage (VSPX) and - wherein the first low-side switch (T _0L ) is connected between the first terminal (X ₀ ) and the reference potential (GND), and - wherein the second low-side switch (T _1L ) is connected between the second terminal (X ₁ ) and the reference potential (GND) u nd - wherein the set signal (SET) is an input signal of the at least one half-bridge controller (1) and - wherein the half-bridge _controller (1) the first half-bridge (T _0L , T _0H ) from the first low-side switch (T _0L ) and first high-side switch (T _0H ) in response to the set signal (SET) controls and - wherein the half-bridge control (1) the second half-bridge (T _1L , T _1H ) from second low-side switch (T _1L ) and second high-side switch (T _1H ) in response to the set signal (SET) complementary controls and - wherein the first high-side measuring device (T ' _0H , T _0RH , V _0H , S _0GND , S ₀ ) at least temporarily the detection of the first high-side switch _current (I _x0H ) by the first high-side switch (T _0H ) is used, and, - wherein the second high-side measuring device (T ' _1H , T _1RH , V _1H , S _1GND , S ₁ ) at least temporarily the detection of the second high-side switch _current (I _x1H ) by the second high-side switch (T _1H ) is used, and, - wherein the current sign is used at least temporarily for detecting the sign of a first Habbrückenlaststroms (I _x0 ) in the first terminal (X ₀ ) of the first half-bridge (T _0L , T _0H ) and a current direction _information determining or generating a current direction signal (CURRDIR) and wherein in the full bridge device, depending on this current direction information or the value of the current direction signal (CURRDIR), either one by the first high side measuring device (T ' _0H , T _0RH , V _0H , S _0GND , S ₀ ) detected value of the first high-side switch _current (I _x0H ) by the first high-side switch (T _0H ) or by the second high-side measuring device (T ' _1H , T _1RH , V _1H , S _1GND , S ₁ ) value used by the second high-side switch current (l _x1H ) by the second high-side switch (T _1H ) as the current reading of their current measurement at its output (X ₀ ) or provides. Current sign detecting device (2,3,4,5,6,7) for a full bridge device according to claim 4 - with a high-side comparator (2) and - with a low-side comparator (3) and - with a delay counter (4 ) and - with a memory (5) and - with a further memory (6) and - with a comparison stage (7), - wherein the high-side comparator (2) the potential at the output (X ₀ ) of the first half-bridge ( T _0H , T _0L ) is compared with a further reference value (V _s -V _ref ) or high-side threshold value and generates a LOW-HIGH delay value (VDSH), and - wherein the low-side comparator (3) the potential at Compares output (X ₀ ) with a reference value (V _ref ) or low-side threshold value and generates a HIGH-LOW delay value (VDSL), and - wherein the delay counter (4) determines the time between an edge of the set signal (SET) and the corresponding edge at the output (X ₀ ) of the first half-bridge (T _0L , T _0H ) detected and - wherein the memory (5) by the Verz ogerungszähler (4) detected time from the edge of the set signal (SET) to the rising edge at the output (X ₀ ) of the first half-bridge (T _0L , T _0H ) stores as a memory _value and - wherein the further memory (6) one through the Delay counter (4) recorded time from the opposite edge of the set signal (SET) to the falling edge at the output (X ₀ ) of the first half-bridge (T _0L , T _0H ) as a further memory value stores and - Wherein the comparison stage (7) from the Memory value in the memory (5) and the further memory value in the further memory (6) determines the current direction information or generates the current direction signal (CURRDIR). Method for determining the load current (IL) in an inductive load (L) or out of an inductive load (L), which between the first output (X ₀ ) of a first half-bridge (T _0H , T _0L ) with a first High-side switch (T _0H ) and with a first low-side switch (T _0L ) and the second output (X ₁ ) of a second half-bridge (T _1H , T _1L ) with a second high-side switch (T _1H ) and with a second low-side switch (T _1L ), comprising the steps of - providing a set signal (SET); Generating a first edge on the set signal (SET); Generating a falling edge at the first output (X ₀ ) of the first half-bridge (T _0H , T _0L ) with a first delay time in temporal relationship with the first edge and detecting this first delay time and generating a rising edge at the second output (X ₁ ) the second half-bridge (T _1H , T _1L ) in temporal relationship with the first edge; - Generating a second edge on the set signal (SET), which is opposite to the first edge; Generating a rising edge at the first output (X ₀ ) of the first half-bridge (T _0H , T _0L ) with a second delay time in temporal relationship with the second edge and detecting this second delay time and generating a falling edge at the second output (X ₁ ) the second half-bridge (T _1H , T _1L ) in temporal relationship with the second edge; - forming the difference between the first detected delay time and the second detected delay time; - Determining whether the first low-side switch _current (I _x0L ) by the first low-side switch (T _0L ) or the second low-side switch _current (I _x1L ) by the second low-side switch (T _1L ) is to be measured as a representative of the load current (IL) as a function of this difference; - Measuring the selected switch current (I _x0L , I _x1L ) as a representative of the load current (I _L ) and output or provision of a corresponding load current measurement. Method for determining the load current (IL) into an inductive load (L) or out of an inductive load (L) which is connected between the first output (X ₀ ) of a first half-bridge (T _0H , T _0L ) with a first high Side switch (T _0H ) and with a first low-side switch (T _0L ) and the second output (X ₁ ) of a second half-bridge (T _1H , T _1L ) with a second high-side switch (T _1H ) and with a second low-side switch (T _1L ), comprising the steps of - providing a set signal (SET); Generating a first edge on the set signal (SET); Generating a falling edge at the first output (X ₀ ) of the first half-bridge (T _0H , T _0L ) with a first delay time in temporal relationship with the first edge and detecting this first delay time and generating a rising edge at the second output (X ₁ ) the second half-bridge (T _1H , T _1L ) in temporal relationship with the first edge; - Generating a second edge on the set signal (SET), which is opposite to the first edge; Generating a rising edge at the first output (X ₀ ) of the first half-bridge (T _0H , T _0L ) with a second delay time in temporal relationship with the second edge and detecting this second delay time and generating a falling edge at the second output (X ₁ ) the second half-bridge (T _1H , T _1L ) in temporal relationship with the second edge; - forming the difference between the first detected delay time and the second detected delay time; - Determining whether the first high-side switch _current (I _x0L ) by the first high-side switch (T _0H ) or the second high-side switch _current (I _x1H ) by the second high-side switch (T _1H ) is to be measured as a representative of the load current (IL) as a function of this difference; - Measurement of the selected switch current (I _x0H , I _x1H ) as a representative of the load current (I _L ) and output or provision of a corresponding load current measurement.

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