DE19754903C1 - Replacement circuit for several similar function modules - Google Patents

Abstract

The replacement circuit uses electronic switching devices (S1,S2,..,S21,S22,...) connected to the inputs and outputs of several similar function modules (F1,...F8) for processing a number of signals. The switching devices are coupled to a replacement function device (FP). A control logic (SL) provides the replacement priority for the function modules in the event of simultaneous failure of a number of function units, independent of a control processor (PU).

Description

The invention relates to an equivalent circuit for several Sig nale processing identical functional units according to the waiter Concept of claim 1.

To increase operational safety, it is known to everyone Functional unit to provide an equivalent circuit. In the event of failure a functional unit is this out of the signal path separates, and a corresponding replacement functional unit is switched on in their place.

From DE 195 28 742 C1 it is known a single replacement function for several functional units to provide unit. This will reduce the circuitry and thus significantly reduced costs. There are only a few Loss of security compared to the so-called 1: 1 Pro tection, since it is extremely unlikely that several Functional units fail at the same time.

For switching between one of the functional units and the Replacement functional unit are with PIN diodes (as a switch used diode that an intrinsic zone between a p-lei tendency and an n-conducting zone) built Um switch in use, the inputs of the functional unit upstream and the outputs of which are connected downstream. With a larger number of functional units, the Switching over a combination containing an additional switch nation switching. The changeover is controlled by a control logic causes the control signals from the Receives functional units.

With optional or retrofitted equipment with an Er However, the structure is suitable  niger because of a considerable number of control and signal lines between the individual modules is required.

The invention according to claim 1 is based on the problem an optional or add-on equivalent circuit specify.

The particular advantage is that no electrical Connections between one also for tax and over computing unit and the protection Assembly is required on which the switch and the Control logic are arranged. Since the functional units Switches are connected upstream or downstream and signals The Pro is not just branched off on the modules tection device even with faulty entry and exit gear shifts effective. In a simple embodiment the equivalent circuit for signals of a first category, for example on the transmission side, directly from the Functional units controlled without the control computer must grab.

In other applications, it is appropriate that the Functional units separate error messages on the control computer, which is initially an equivalent circuit for Sig nale of the second category, for example for a Kop signals carried by pelfeld, carried out and only afterwards by releasing the error messages of the functional units or a special control signal the equivalent circuit for Sig of the first category.

With bidirectional processing of Sig nalen in a functional unit the generation of a single Control signal for both processing directions, since here due to the effort for the control logic and switching device gene is reduced.  

Is the equivalent circuit on the protection module from Control computer controls can provide more targeted information won over the type of fault and unnecessary switching operations be avoided.

In the unlikely failure of multiple functional units is an equivalent circuit according to a specified Priority made. Because of certain errors the funct ons unit of the control computer their control signal no longer it can be advantageous that the control logic itself - according to the priority - the radio to be replaced unit determined and the control computer via the replacement Functional unit determines the time of switching. As Error message, the voltage of the control signal is selected, their occurrence in the event of a hardware failure most likely is z. B. about 0 volts.

If the functional units anyway ver with a switching matrix are bound, it is appropriate to use the equivalent circuit for Sig to control the second category from the control computer and to use the switching matrix as a switch.

If the supply voltage for the Control logic and the PIN diode switch can be obtained the supply of a separate supply voltage is stopped ben.

It is advantageous if there are only two outputs from the input switch merged and this merge point with a further at least two inputs switch (or another decoupling switch ning element) is connected. This will make the signal paths optimally decoupled from each other and the capacitive loading loads kept low.

The invention is illustrated by an embodiment explained.  

Show it:

Fig. 1 is a schematic diagram of the invention,

Fig. 2 is an expanded schematic diagram

Fig. 3 is a diode switch exported and

Fig. 4 is a schematic diagram of the control logic.

The basic circuit diagram shown in FIG. 1 shows bidirectional functional units F1 to F8 and a protection assembly group PB with switches S1, S3,. . ., S15; S2, S4,. . ., S16 and a control logic SL. The toggle switches marked with odd numbers each have one input and two outputs. The first output is connected to an input I1 to I8 of the functional units F1 to F8. The second outputs (from a functional point of view) are brought together and connected to an input IP of a replacement functional unit FP. In the undisturbed case, all incoming signals SI1 to SI8 are fed to the inputs I1 to I8 of the functional units and all outgoing signals SO1 to SO8 are output at the outputs O1 to O8.

The control logic SL receives the control outputs P1 to P8 Functional units and the control output PP of a replacement Functional unit FP control signals CF1 to CF8 and CP, the be evaluated by her. The control logic is so concise piert that only one pair of switches S1 to S16 for incoming and outgoing signals correspond to a fixed one priority can be operated so that only one incoming signal SI1 to SI8 of a first category as Protection input signal SIP on the input IP of the replacement Functional unit is switched and at the protection output OP2 a protection output signal SOP as one of the outgoing signal SO1 to SO8 is output.

The functional units set the incoming signals of the he Most category in output signals SCO1 to SCO8 (related to  the functional units) of a second category (here cross Connect signal with a different data format), which over Outputs O11 to O18 and switches S22, S24,. . . a paddock field CC are forwarded. Via further switches S21, S23,. . . of the switching matrix contain the functional units corresponding input signals SCI1 to SCI8 of the second Kate theory, which in turn converts it into outgoing signals SO1, SO2,. . . in the first category and via outputs O1 to O8 the Functional units and further switches S2, S4,. . . the pro Submit tection assembly. The inputs and outputs of the Functional units for signals of the second category are included the same letter as for signals of the first category however marked with other or additional digits. The bidirectional functional units deliver for both directions of transmission only one Control signal CF1, CF2. . .

In the event of a fault, the for both directions of transmission Signal path switched through the replacement functional unit, which of course also for bidirectional processing is executed.

The functional units and the are via a data bus DB Replacement functional unit with a control computer PU for switching off exchange of control data CD connected. The control computer be also switches S21, S22,. . . of the switching matrix CC. The arrangement can be part of a synchronous multiplexer or a cross connector where Sig signals of a first category into signals of a second category rie be implemented, which then over the switching matrix CC can be ranked; the same happens in the opposite direction.

Depending on the embodiment, several ways of working are the pros tection assembly conceivable. In the simplest case, the order switch of the protection module directly due to the con troll signals CF1 to CF8 controlled. Corresponds to one of these  Control signals of an error message, so the correspond Changed switch, for example S1 and S2 operated and that incoming signal SI1 is used as protection input signal SIP supplied to the replacement functional unit FP, or from this the Protection signal SOP = SO1 accepted. Of course, have to the switching matrix also the corresponding input signal SCI1 = SIP2 of the second category on the replacement functional unit are redirected and the protection signal SOP2 = SCO1 the switching matrix are output.

In the case of another version, the control Error messages contained in the data CD are sent to the control computer leads while the control signals CF1, CF2,. . . the functi ons units despite an existing malfunction stay changed. The control computer checks the error message then leads (if there are several faulty functions units according to priority) the equivalent circuit through in the switching matrix and then causes a match the control signal CF = 0 volts from the malfunction unit is delivered and thus fed to the control logic.

The switchover in the protection module can also first then take place when a corresponding command is sent to the replacement Functional unit is sent, this to output a Control signal CP = Vcc causes the input P of the Control logic is fed. This has the advantage that too if there are several faulty functional units, the control logic un depending on the control computer according to the given one Priority an equivalent circuit for the most important function unit determined and the time by the control computer is determined. A direct connection between the control computer and control logic is never required. This out leadership offers the most advantages.

Fig. 2 shows a more detailed block diagram of the Pro tection module. Only the first four changeover switches S1, S3, S5, S7 and S2, S4, S6, S8 realized with PIN diodes are shown. The first outputs of the switches labeled W (working) are connected to inputs I1, I2,. . . of the functional units connected. The second outputs, designated P, of switch S1 and switch S3 are routed together; the second outputs of switches S5 and S7 are also brought together. Optionally, one of these merging points is connected in a first combination part COM1 via a further switch SW to the input IP ( FIG. 1) of the replacement functional unit FP.

The same combination part for those not shown here Switches S9, S11, S13, S15 of the functional units F5 to F8 and an additional switch is also with the Output of the switch SW connected. The same combination Parts are again for those with even numbers drew switches S2, S4,. . . provided up to S18 - made of green the clarity is not shown.

One issued by a functional unit, for example F1 The correct control signal CF1 is the first switch S1 fed directly. That corresponds to a correct control signal voltage switches a PIN diode of switches S1 and thus the signal SI1 to the functional unit F1. The The control signal is also fed to the control logic.

On the other hand, an error message is issued by the functional unit F1, this is first communicated to the control computer which the switching network switches to the replacement functional unit. At the same time or shortly thereafter, it switches the control signal CF1 to the error state. The incoming signal SI1 is hereby separates from the input of the functional unit F1. Becomes then - prompted by the control computer - the Kon troll signal CP at the output labeled P of the replacement Functional unit set to the state CP = Vcc, so from the control logic a control signal CE1, which the turns on other PIN diode of the first switch and that incoming signal SI1 via the further switch SW to the  Input of the replacement functional unit FP as an input signal SIP switches through. The output signal of the replacement functional unit SOP of the replacement functional unit - it corresponds in this If the output signal SO1 of the intact functional unit F1 - is via another corresponding combination circuit for the outgoing signals and switch S2 tet.

With a self-sufficient Pro independent of a control computer In the event of a fault, the tection module is removed without intervention by the tax calculates the protection path solely from the functional units switched through.

The connections of the functional units to the switching matrix and the data bus was not used for reasons of clarity shown.

In Fig. 3 is a simplified circuit diagram with two Umschal age S1 and S3 and one of the other switch SW Darge presents. The incoming signal SI1 arrives at the cathode of two PIN diodes DS1 and DP1, of which the PIN diode DS1 is switched through in the undisturbed mode of operation (CF1 = V _cc and forwards the incoming signal SI1 to the first functional unit F1. In the event of an error message the control signal CF1 goes to logic zero and the first PIN diode DS1 blocks the PIN signal DP1 is switched through by the control signal CE1 so that the incoming signal reaches the merging point ZP1, which in turn is connected to one input of the other Switch SW formed from PIN diodes DP1, DP2, which is controlled via the diodes Z1 and Z2 and switches the incoming signal - now designated SIP - to the replacement functional unit.

However, if the third or fourth functional unit is defective, so the corresponding incoming signal is sent over a two th merge point ZP2, not shown switches.  

By combining the control signals via Zener diodes - the voltage regeneration PR - "Power Regeneration" - becomes the supply voltage VCC for the control logic and the Switching voltage of the control signals obtained.

In Fig. 4 a detail of the control logic SL is Darge provides. It is constructed in such a way that in the case of several defective functional units, the one with the highest priority - here the functional unit F1 - is replaced. A faulty function module F1 is signaled in that the control signal OF1 goes to logic zero. This signal is inverted by the first inverter IN and - as soon as the control signal CP of the replacement functional unit is set to logic one - the first control signal CE1 (logic 1) is generated via the AND gate ANDI, which switches the first order actuated, more precisely the PIN diode DP1 ( Fig. 3) switches through. The control signal OF1 prevents NOR1, NOR2,. . . that further control signals can assume the state of logic one. If, on the other hand, the second functional unit is defective (CF2 = 0), the control signal CE2 is generated via the AND gate AND2 and prevented via an inverter IN1 and the AND gate AND11 that further changeover switches are actuated via the further control signals CE3 to CE8 can be. Of course, numerous circuit variants are possible.

Claims (8)

1. Equivalent circuit for several identical functional units (F1 to F8), the inputs (I1, I2,... 18) for incoming signals (SI1, SI2,... SI8) of a first category each an electronic switch (S1, S3, S5, S7) is connected upstream, so that one of the incoming signals (SI1, SI2, ... SI8) can be routed to the input (IP) of a replacement function unit (FP) via second outputs of the changeover switch, and that outputs (O11 , O12,...) Of the functional units (F1 to F8) for output signals (SCO1, SCO2,...) Of a second category are each followed by a switch (S22, S24,...), Via whose second inputs protection -Output signal (SOP2) of the replacement function unit (FP) instead of an output signal (SCO1, SCO2,...) Of the second category can be supplied, and in which the equivalent circuit is carried out by a control logic (SL), characterized in that a Control computer (PU) is provided, which via a data connection (DB) is connected to the functional units (F1 to F8) via which the functional units (F1 to F8) give error messages to the control computer (PU) that the control computer (PU) switches (S22, S24,. . .) controls for outgoing signals of a second category and that the functional units (F1 to F8) control signals (CF1 to CF8) are passed to the control logic (SL), which switches (S1, S3, ... S15) for incoming signals controls the first category. 2. equivalent circuit according to claim 1, characterized in
that the functional units (F1 to F8) are designed for processing signals of the first category (SI1 to SI8; SO1 to SO8) and signals of the second category (SCI1 to SCI8; SCO1 to SCO8),
that a single control signal (CF1, CF2,...) is emitted by each functional unit (F1 to F8),
that further switches (S21, S23,...) for input signals of the second category (SCI1 to SCI8) are connected upstream of further inputs (I11, I12,...) of the functional units (F1, F21,...), via which a Input signal of the second category to a further protection input (IP2) of the replacement function unit (FP) can be switched over so that the control computer (PU) switches (S21, S23,...; S22, S24,...) For incoming and controls outgoing signals of a second category,
that further changeover switches (S2, S4,...) for outgoing signals of the first category (SO1, SO2,...) are connected to further outputs (O1, O2,...) of the functional units, via which a further protection Output signal (SOP) of the replacement function unit (FP) can be switched, and that all switches (S1, S2, S3, S4, ...) for incoming and outgoing signals of the first category (SI1 to SI8; SO1 to SO8) from the control logic (SL) can be operated. 3. equivalent circuit according to claim 1 or claim 2, characterized, that the functional units (F1, F2...) are designed in this way are that they have the data link (DB) with the tax computer (PU) can receive commands through which the state the control signals (CF1, CF2,...) is changed. 4. equivalent circuit according to claim 3, characterized, that the control computer receives the control signal (CP) of the replacement Functional unit (FP) activated via the control logic (SL) first performs an equivalent circuit. 5. equivalent circuit according to one of the preceding claims, characterized in
that the functional units (F1, F2,...) are designed in such a way that a voltage of approximately 0 volts is emitted as a control signal (CF1, CF2,...) in the event of a fault,
that the control signals (CF1, CF2,...) are brought together via diodes,
that from the control signals (CF1, CF2,...) a supply voltage (Vcc) for the control logic (SL) and a switching voltage for the changeover switch (S1, S2,...) is obtained. 6. equivalent circuit according to one of the preceding claims, characterized, that as an electronic switch (S1, S2,...) PIN diodes switches (DS1, DP1) are provided. 7. equivalent circuit according to one of claims 1 to 6, characterized, that the control logic (SL) is designed such that it several error messages according to a given one Priority the equivalent circuit for only one of the Functional units (F1, F2, F3,...) Performs. 8. equivalent circuit according to one of claims 1 to 6, characterized, that the switch (S21, S22, S23,...) for signals of second category belong to a switching matrix (CC) and that the Control computer (PU) with several error messages accordingly the priority is an equivalent circuit by sole change the control signal (CF1) of the highest priority Functional unit (F1) performs.