TWI313960B - A half bridge inverter - Google Patents

Description

1313960

IX. Description of the invention: [Technical field to which the invention pertains] A half-bridge converter device, in particular, a converter device that can control a half-bridge converter using a push-pull control wafer and drive a load. [Prior Art] The power supply of the TFT panel backlight mainly uses an inverter circuit to achieve energy conversion and drive the illumination of the cold cathode fluorescent lamp (CCFL). The conventional converter circuit (InverterCircuit) is divided into a half-bridge converter circuit, a full-bridge converter circuit, and a push-pull converter circuit due to the difference in circuit topology. The system converts direct current into alternating current. The commutation path. The reference diagram of the month is a circuit diagram of a conventional push-pull converter circuit applied to the Ccfl load. The transformer T1# divides the circuit into a primary side prior circuit, a 1〇1 and a primary side subsequent stage circuit 1〇2. The pre-stage circuit J(1) includes:

A control signal b controls the output of the chip 103 of the front stage circuit 101, wherein the first switch Q1 of the first control signal a 101 and the 1313960 __ _ 丨 replace the switch of the second switch Q2, and according to the DC power supply The voltage of Vcc is used to supply energy and the voltage of the DC power supply Vcc is boosted and converted by the transformer T1. To the secondary side of the transformer T1, for driving the load (L〇ad), the secondary side output voltage waveform of the transformer T1 The c system displays the voltage waveform at point C. As shown in the second figure, the secondary side output voltage waveform c of the transformer T1 is an alternating current voltage waveform. In the above description, the push-pull control wafer 103 is a wafer produced by UNFINITY (MICROSEMI), and its model is LX1686 surface and LX1_ and LX1691 series, or is a wafer produced by 02 Micro intemati〇nal Limited. 2_9RR, 〇Z993〇, 〇Z9938, 0Z9939 and TEXAS INSTRUMENTS wafers, model TL 494, TL-594, model number, and Beyond Innovation Teehnology wafers, models BIT3193, BIT3713, ΒΓΓ3715, Series BIT35〇l and so on cannot be used because of the comprehensive number of labels - for example, only listed by common models. _Please refer to the third figure, which is the circuit of the conventional half-bridge converter circuit to drive the load. The transformer T2 divides the circuit into a primary side pre-stage circuit 2〇1 and a secondary side subsequent stage circuit 2〇2, and the pre-stage circuit 2〇1 includes: a DC power supply VCC, an electronic switch (Q1, Q2), and a half. The bridge control chip TL494, the two turtles (Cl, C2) and a drive transformer are equal, and the rear stage circuit 202 includes: a load. Referring to the third figure, together with the fourth figure, it is a schematic diagram of the output control signal and the AC power supply voltage waveform of the conventional half-bridge control chip. The half-bridge control chip TL494 is controlled by two round-out terminals D and D2, and the control signal D1-D2 is rotated. The control signal 1313960 'year and month correction replacement page 98. 5. Q1, Q2 two electronic open bodies or p, two guilty solid electronic switches Q1, Q2 are N-channel field effect electric crystal ^^, ^^ electric crystal fj # by the two electronic switches Q1, Q2 switching ^Electrical power 3 (1) C2 power transmission - cross-connect capacitor C3 points ac. The electric power capacity device is the sub-terminal T21 for forming an AC power supply. The sixth voltage: the voltage of the C2 is the DC power supply Vcc - the half voltage Vcc/2. Second = the power supply AC is used to supply energy to the transformer Τ2, and the booster is converted to the secondary side of the transformer Τ2 by the transformer D2, which is used to drive the load hopper. In the case of the month, if the converter circuit is used (InverterCircuit) When it is a half bridge, it needs to be controlled with a half bridge control chip. # = Free mode needs to be controlled with the push-pull control chip.

Clrc t ) 2 lacks flexibility and systemicity. Furthermore, the commutation circuit (1 is also limited by the control chip, resulting in the commutation circuit and the second ir<T) because of the above-mentioned condensed description, so that the control chip can not be shared, and the first purchase Material, or need to match more complex circuits. At the same time, 'Xi (four) half-bridge converter circuit needs to be converted to _ to 'can' * bridge control chip directly drive the fine, the former / hold the know-how half-bridge converter circuit using the electronic open relationship is the same (four) handle power The crystal is composed of a P-channel field effect transistor or a p-channel field effect transistor and an N-channel field effect transistor. SUMMARY OF THE INVENTION In view of the above, the present invention provides a half-bridge converter-drive circuit connected to the output end of a push-pull control chip and a two-channel switch-effect transistor composed of a half-bridge switch module. The _ circuit accepts the control of the subtractive control chip to drive the switching action of the half-bridge switch assembly. The present invention is a half bridge type commutation device which is connected between two electronic switches of a conventional half bridge type switching circuit and a control chip. :

And the control wafer is replaced by a push-pull control wafer, thereby controlling the switching operation of the two sub-switches. In the above, the half-bridge converter device provided by the present invention is provided with a push-pull control crystal of the Han-first output terminal and the second output terminal. The output duty ratio of the slice is less than 5_the first control signal and the second control signal '----, the remaining to the reference terminal, and the through-first circuit - the first of the push-pull control chip - Output terminal; - current limiting power 2 = in the first switch and the DC power supply; - second _, the vehicle is connected to the 苐 1_ the reference terminal ' and the current limiting power is reduced by the current limiting power; - SCR switch The gate of the SCR switch is lightly connected to the second switch. The anode of the SCR_ is secretive to the DC power source; the first field-effect transistor has a gate connected to the cathode of the SCR switch, and is lightly connected to the cathode. The DC power source has a source reduced from the secondary side of the transformer; and a second N-channel field effect transistor having a gate connected to a second output of the push-pull control day and day chip At the end, the splicing two = one N-way 迢 field effect electric crystal secret, its source county to make the reference end. 1313960

Si, such a semi-bridge converter device of the present invention uses a driving circuit for a conventional half-bridge converter circuit, that is, it can be controlled by using a push-pull control crystal chip, which is more flexible in practical use. It is not limited to the control chip. Moreover, the operator can drive and control the push-pull converter circuit or the half-bridge converter circuit according to actual needs by simply using the push-pull control chip. The above summary and the following detailed description are exemplary in order to further illustrate the scope of the claims. Other objects and advantages of the invention will be set forth in the description and drawings. [Embodiment] Please refer to FIG. 5, which is a circuit diagram of a half bridge type switching device according to a first embodiment of the present invention; The half bridge converter device of the first embodiment of the present invention is connected to the primary side of a transformer T2 for converting the DC power source Vcc into an AC power source AC, and the AC power source AC provides a load LOAD action through the transformer T2. The energy needed. Referring to the fifth figure, the half-bridge converter device of the first embodiment of the present invention has a push-pull control chip 103, a first buffer circuit 34, a second buffer circuit 36, and a driving circuit. 30 and half bridge switch assembly 32. The push-pull control chip 103 is provided with a first output end a and a second output end B. The first output end person and the second round end B respectively have a duty cycle of less than 50%. A first control signal a and a second control fb. The first buffer circuit 34 is absent from the first wheel end A of the push-pull control chip 1〇3; the second buffer circuit 36 is coupled to the second output end of the push-pull control 10 1313960 wafer 103 B; the driving circuit 30 is lightly connected to the first output terminal a of the push-pull control chip 1〇3 and the 5 VDC power supply Vcc through the first buffer circuit 34, and receives the first control signal a; the half bridge The switch button member 32 is composed of two channel field effect transistors (Q1, Q2), the half bridge switch module 32 is coupled to the DC power source Vcc, the driving Thunder =, the second buffer circuit 36 And the transformer T2 'the half bridge type switch group is controlled by the driving circuit 30 for transmitting the direct current to the alternating current power source AC to the transformer (four) - the second side of the original knife is replaced with reference to the fifth figure The driving circuit 30 includes: a first switch first-electric*" and R3, a second switch Q5 and an SCR switch Q3. The switch Q4 is connected to the first buffer circuit 34 and is connected to the first switch and the DC power source VCC; the switch Q5 is coupled to the first switch Q4 and the reference terminal _ to be connected to the reference terminal _ The DC power supply ^; the _ off core (4) is coupled to the second switch Q5 'the paste switch Q3 yang - the power supply VCC, the clear switch Q3 cathode (1) is after the 5 hai + bridge switch assembly 32. The channel=half bridge switch assembly 32 includes a -N-th pass t Q1 and a second N-channel field effect transistor. The pole U) transistor Q1 is extremely lightly connected to the SCR switch, the cathode power supply VcJ: the N-channel field effect transistor Q1 is connected to the DC voltage source, the N-channel field effect transistor Ql source The pole is coupled to the primary side of the variable ° 2 . The gate of the first channel field effect transistor 92 is transparent

Vn\ 11 1313960 —____________ — . PAGE _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The drain of Q2 is coupled to the source of the first channel field effect transistor Q1, and the source of the first channel field call crystal Q2 is coupled to the reference terminal gnD. In the above, the DC power supply provides a positive DC power supply + Vcc to the transformer T2 via the conduction of the first N-channel field effect transistor Q1 to form a positive half-cycle drive or via a second N-channel field effect transistor Q2. The conduction 'provides a negative DC power supply' - Vcc gives the transformer T2 to form a negative half cycle drive. Referring to the fifth figure, the first buffer circuit 34 includes a first-accelerator diode D1 and a first resistor R1. The negative (N) terminal of the first acceleration diode D1 is coupled to the first output terminal A of the push-pull control chip 1〇3, and the k-pole (P) terminal is coupled to the first switch Q4. The first resistor R1 is connected in parallel to the first accelerating diode D1. The second buffer circuit 36 includes: a second accelerating diode D2 and a second resistor R2. The negative (N) end of the second accelerating diode D2 is coupled to the second output Φ end B of the push-pull control chip 1〇3, and the positive (P) end is coupled to the second N-channel field effect transistor q2 The gate. The second resistor R2 is coupled in parallel to the second acceleration diode! )2. Referring to the fifth embodiment, the half-bridge converter device of the present invention further includes a capacitor C1 coupled between the gate and the source of the first N-channel field effect transistor Q1. Capacitor C1 can be added to the device depending on the needs of the circuit characteristics. In the circuit design, the electric grid device Ci can be replaced by one of the first n channel % effect transistor Q1 gate-source interpole capacitance CGS. With reference to the fifth figure, please refer to the ninth figure. The ninth figure is a schematic diagram of the push-pull 1313960 type control chip output signal and the AC power supply voltage waveform of the present invention. The push-pull control chip 103 is a chip produced by LINFINITY (MICROSEMI), and its model is LX1686 and LX1688 and LX1691 series, or the chip produced by 02 Micro international Limited, the models are 02-9RR, OZ9930, 0Z9938, 0Z9939 and TEXAS INSTRUMENTS wafers, model number H-494, TL-594

The models are listed as 'wafers manufactured by Beyond Innovation Technology'. The models BIT3193, BIT3713, BIT3715, BIT3501, etc. are not available because of the many brands - for example, only the common models. . As shown in the ninth figure, the output terminal A of the push-pull control chip 103 outputs the first control signal a, and the output terminal B outputs the second control signal b. Moreover, the voltage waveform of the AC power supply can be obtained on the secondary side of the transformer T2. Referring to the fifth figure, referring to the ninth figure, at time t t2, the first control signal a is high and the second control signal b is low. The first control signal a is transmitted to the first switch through the first buffer circuit 34 to control the first switch Q4 to be turned on ((10)). The turned-on switch 11 slave couples the control terminal of the second switch Q5 to the reference terminal G to maintain the off state. The cut-off second switch Q5 causes the gate (6) of '= to form a floating (fl(Dating) state), at which time the DC Vcc will cross between the anode a and the cathode κ of the SCR switch Q3, and the book ", SCR switch Q3 Enter the conduction ((10)) state. With the SCR switch $ON, the i-stream power supply Vcc drives the first-N channel field effect transistor into the ON state. Ba _ yi 1313960 r Ice · π r 98^. In addition, the low potential second control signal b is transmitted through the second buffer circuit 36.

Transfer to the gate of the second]\|channel field effect transistor q2 to control the second N-channel field effect transistor Q2 cutoff (〇FF). Therefore, at the time u~t2, the Nth field field effect transistor milk is in the on state (〇N) state, and the second N channel field effect transistor Q2 is in the off (0FF) state. At this time, the DC power source Vcc can be turned on (第一N) through the first N-channel field effect transistor Q1, and the energy is sent to the secondary side of the transformer T2 and the resonant capacitor C2.

The voltage wave shape obtained by the secondary side - the secondary side is a positive DC power supply + and forms a positive half cycle drive. At this time, the two ends of the resonant capacitor c2 establish a DC voltage. With reference to the fifth figure, referring to the ninth figure, at time t2-t3, the second control signal & is lowered from the high potential to the low potential, and the second control signal 1) remains at the low potential. At this time, the first switch Q4 is accelerated to enter the OFF state by the first-accelerator diode D1, and the DC power source and We control the second switch q5 to enter the conductive (10)-like green state through the current limiting resistor R3. The second switch Q5 that is turned on is the gate (G) _ ground terminal (10) of the SCR switch Q3. According to the characteristics of the SCR switch Q3, the SCR switch (10) is turned off ((4)) cancer, so the first-N channel field effect power Crystal Q1 enters the banknote (which) state. Since the second control signal b remains at a low potential, the second N-pass field effect transistor Q2 is still cut off (〇FF)-shaped bear. As can be seen from the above description, at time t2-t3, the second N-channel field The effect of the electric crystal (10) and the second N-channel field effect transistor state causes the primary side of the transformer T2 to form an open circuit. At this time, the voltage waveform ac obtained by the 8.1 times side of the 1313960 9 years is zero potential. Referring to the fifth figure, referring to the ninth figure, at time t3-t4, the first control signal a remains low. The second control signal b rises from a low potential to a south potential. The first control signal b is transmitted to the gate of the second N-channel field effect transistor Q2 through the second buffer circuit 36 to control the second n-channel field transistor Q2 to be turned on (0N). Since the first control signal a remains at the low potential, the first N-channel field effect transistor Q1 is still in the off state.

At this time, the first N-channel field effect transistor qi is in the off (0FF) state, and the first N channel field effect transistor Q2 is in the on state ((10)) state. At this time, the DC voltage built on the two ends of the resonant capacitor C2 is transmitted to the primary side of the transformer π according to the second (NN) field effect transistor q2 that is turned on (0N), and the voltage waveform obtained by the transformer Τ2-second side is obtained. The buckle is a negative DC power supply, Vcc 'and forms a negative half cycle drive.

Referring to the fifth figure, referring to the ninth figure, at time 15, the first control signal a is still low, and the second control signal is from high potential to low. At this time, the first-N channel field effect transistor Q1 and the second N field effect transistor Q2 are in the off (10) state, and one of the transformers T2 is turned off. At this time, the voltage waveform obtained by the primary side of the transformer Τ2 is the fifth diagram of the lightning system of the system. Referring to the ninth diagram, the half-bridge converter of the present invention is replaced by the road-driven device and the device 2: At 6 o'clock, the action and waveform of the Japanese phase called 2 o'clock were repeated. The above-mentioned Zhu Ming expressed the AC power supply AC. At the same time, 15 1313960 rigorous pager T2 will AC power AC 懕 垃 垃 y you y to load α_. After the liter 1 conversion, the half of the energy is supplied from the secondary side: t is the sixth figure, which is the second embodiment of the present invention: the schematic diagram of the circuit. In the second embodiment of the present invention, the same as the first embodiment are denoted by the same reference numerals. The circuit operation principle of the second real-first embodiment is the same as that achieved by the second embodiment. The main difference is that the second embodiment replaces the second switch Q5 in the first real-world with the optical coupling switch. The circuit components in the half-bridge converter are protected by the switching characteristics of the optical coupling switch. With reference to the fifth drawing, please refer to the seventh figure, which is a circuit diagram of the +bridge type reducing device of the third embodiment of the present invention. The components in the third embodiment of the present invention are the same as those in the first embodiment, and are denoted by the same reference numerals. The circuit operation principle of the third embodiment is the same as that of the first embodiment. The main difference between the third embodiment and the second embodiment is that the third embodiment uses the SCR switch Q3 in the first embodiment as -pnp. The transistor (10) is surface-connected with an NpN transistor Q32 equivalently substituted. With reference to the fifth figure, please refer to the eighth figure, which is a circuit diagram of the half-bridge converter device according to the fourth embodiment of the present invention. The components in the fourth embodiment of the present invention are the same as those in the first embodiment, and are denoted by the same reference numerals. The circuit operation principle of the fourth embodiment is the same as that of the first embodiment. After comparison, the main difference is that the fourth embodiment uses the second switch Q5 in the first embodiment as an optical coupling switch. Instead, the circuit components in the half-bridge converter are protected by the switching characteristics of the optical coupling switch. At the same time, the fourth embodiment 16-equivalently replaces the SCR switch Q3 of the first embodiment with a ρΝρ electric crystal Q31 coupled to a crystal Q32. Further, in the fourth embodiment, the first switch Q4 in the first embodiment is replaced with a - bipolar transistor switch (BJT). In addition, the first buffer circuit 34 uses only the first resistor illusion. In summary, the half-bridge converter device of the present invention can be connected to the drive circuit 30 in a conventional half-bridge commutation f-path, which can be controlled by using a push-pull control chip 103, which is more flexible in practical use. And is not limited by the control chip. And the industry only needs to use the push-pull control chip (10) to control the depreciation tree or the half-flow converter circuit according to actual needs. "Quasi' is merely a detailed description of the specific embodiment of the present invention, the field $ and the schema 'anyone skilled in the art' can easily change in the field of the invention or Modifications can be covered in the scope of the patents in this case below. [Simple diagram of the diagram] The general diagram is a circuit diagram of the conventional push-pull converter circuit to drive the load; the first figure is a schematic diagram of the conventional push-pull control chip output control signal and the load terminal output voltage waveform; A schematic diagram of a circuit for driving a load by a conventional half-bridge converter circuit; the fourth figure is a schematic diagram of a conventional half-bridge control chip output control signal and an AC power supply voltage waveform; and the fifth figure is a half bridge type change of the first embodiment of the present invention Circuit diagram of the flow device;

17 1313960

The sixth figure is a circuit diagram of the half-bridge converter device according to the second embodiment of the present invention; and the seventh figure is a circuit diagram of the half-bridge converter device according to the third embodiment of the present invention. 8 is a schematic diagram of a circuit of a half-bridge converter device according to a fourth embodiment of the present invention; and a ninth diagram of the output signal of the push-pull control chip of the present invention and a waveform of an AC power source voltage.参 [Main component symbol description] Convention: 101 pre-stage circuit 102 post-stage circuit 103 push-pull control chip Τ 1 transformer a first control signal b second control signal c transformer Τ 1 secondary side output voltage waveform 201 pre-stage circuit 202 After-stage circuit T2 Transformer TL494 Half-bridge control chip D1-D2 Output control signal 18 1313960 Q1 First switch Q2 Second switch AC AC power supply _ 0 103 Push-pull control chip 30 Drive circuit 32 Half-bridge switch assembly 34 First buffer circuit 36 Second buffer circuit GND Dream test terminal C1 capacitor LOAD Load AC AC power supply Vcc DC power supply T2 Transformer C2 Resonant capacitor Μ.9% Replace, -:^

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Claims (1)

1313960, a correction replacement page 申请, the scope of application for patents: - . . type of half-bridge converter, connected to - transformer - times ♦ will convert the power supply to an AC power, including:,,, '. m: a chip having a -first output terminal and a second output terminal, wherein the output terminal and the second output terminal respectively output a duty ratio of less than 5_one control signal and a second control signal; Configuring a reference terminal and the push-pull control chip - - 'delivering the first - opening the DC minus the first switch and the reference creep, and the coupling limit resistor are coupled to the DC power supply The switch is freely connected to the second switch, wherein the % pole of the switch is coupled to the DC power source; the utility transistor, the cathode of the first N-channel field effect transistor, and the cathode of the closed Si 1 , the first-N The channel field effect transistor is not connected; the direct 'Qianyuan' source side of the N-channel field effect transistor is connected to the primary side of the transformer; and the f琢 discharge a曰 body' the second N channel field effect The gate of the transistor pushes the second round of the output of the wafer, and the fourth channel field is in the first -N channel field The source of the effect transistor, the source of the N-N channel field effect transistor to the reference end. 2. If the half-bridge type greening device described in the application for turning over the face is applied, the needle source is turned on by the conduction of the first-N channel field effect transistor, and the positive DC power supply is provided. To form a positive half cycle drive. 3. The half-bridge converter device of claim i, further comprising a -resonant capacitor, the resonant capacitor being input to the varietal of the varietal The half bridge type is described in which the resonant capacitor provides a negative DC transformer to form a negative half cycle drive via conduction of the first channel field effect transistor. 5. The half bridge type commutation device according to claim 1, wherein the step further comprises: a first buffer circuit, the first buffer circuit comprising: a first acceleration diode, the negative (8) terminal minus The push-pull control chip-output terminal has its positive (Ρ) terminal connected to the first switch; and the first resistor is connected in parallel to the first acceleration diode. 6. If you apply for the half-bridge converter device described in _ 丨 ,, the second snubber circuit, the second snubber circuit includes: ^一加迷-极体's its negative (Ν) end Connecting the first output end of the push-pull control to have a positive (Ρ) terminal coupled to the gate of the second channel field crystal; and a first tapping electrical resistance coupled in parallel to the second acceleration diode body. The half bridge type commutating device according to the invention of claim 5, wherein the capacitor is connected to the source of the first channel field. The sluice gate of the Japanese version of the invention, wherein the SCR can be equivalently composed of a ΡΝΡ-transistor coupled to a ΡΝΡ transistor. Open. If the application is to turn over the first half of the bridge, the first open 21 1313960 can be a bipolar transistor switch. The </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> Khan 11. A half-bridge converter, connected to the primary side of a transformer, converts the power supply to an AC power source, including: L-Push? The control chip is provided with a first output end and a second output end, and the second output end and the second output end respectively output a first control signal and a second control signal having a duty ratio of less than 50%; The second snubber circuit is connected to the first output end of the push-pull control chip; the second buffer 'wheel is at the second output end of the push-pull control chip 'a drive Wei' ____ circuit chick The _subtractive control chip output terminal and the DC power source receive the first control signal, wherein the driving circuit comprises: a first switch coupled to the first buffer circuit and a reference terminal; In the [off and the DC power supply; = switch is interesting to the first switch and the reference terminal, and is coupled to the DC power supply through the limit; and = switch 'the gate of the SCR switch _ a second switch, wherein the anode of the yarn is switched to the DC power source; and the component is composed of two N-channel field effect transistors, the half 22: and coupled to the DC power source, the driving circuit SCR shuts down the components and the secrets, the half-bridge starts working The dynamic circuit is used to switch the DC power supply to the 22 1313960 moon repairing poverty, .丨 _98, standby, -:·^-ί AC power is transmitted to the primary side of the transformer. 12. The half-bridge converter device of claim 11, wherein the SCR switch is equivalently formed by a germanium transistor coupled to a germanium transistor. 13. The half bridge converter device of claim 11, wherein the first switch is a bipolar transistor switch. 14. The half bridge converter device of claim 11, wherein the second switch is an optical coupling switch. #15. The half-bridge converter device of claim 11, further comprising a capacitor coupled between the gate and the source of the first channel field effect transistor. The half bridge type commutation device of claim 11, further comprising a resonant capacitor coupled to the primary side of the transformer. 23 (S) 1313960 D1-D2 Q1 Q2 Ycc/2 AC -Vcc/2 Figure 4 (Practical Technology)