Driving circuit and power supply module of DC / DC converter

Abstract

The utility model relates to an electronic circuit technology, and discloses a drive circuit and a power supply module of a DC / DC converter, comprising a first power supply end, a square wave generating unit, a first trigger, a second trigger and two drive units, the first power supply end is electrically connected with the power supply ends of the square wave generating unit, the first trigger and the second trigger respectively, and the two drive units are electrically connected with the square wave generating unit. The signal output end of the square wave generation unit is electrically connected with the clock end of the first trigger; the signal output end of the first trigger is electrically connected with the clock end of the second trigger; two signal output ends of the second trigger are electrically connected with input ends of the two driving units respectively; and same-frequency signal output ends with phase difference are arranged between the two driving units and are respectively used for connecting control ends of corresponding switch tubes in the plurality of DC / DC converters which are connected in parallel in an interleaving manner. The utility model aims to improve the power density of the DC / DC converter in a low power consumption mode.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, in particular to a driving circuit and a power supply module of a DC / DC converter. Background Art

[0002] For some power supply systems (such as avionics systems) with complex and changeable power supply networks and large stable voltage differences between the front-stage high-voltage input and the back-stage low-voltage requirements, in order to achieve large voltage changes between the front and back stages, an isolated non-regulated DC / DC converter is generally added in the middle.

[0003] At present, by increasing the operating frequency of the LLC resonant converter in the DC / DC converter, the volume of the magnetic components can be significantly reduced, which is conducive to the improvement of the power density of the DC / DC converter. However, the increase in switching frequency also means the increase in the loss of related switch tubes (such as MOS tubes) in the LLC resonant converter. Therefore, a low-loss power density improvement method is urgently needed.

[0004] The above contents are only used to assist in understanding the technical solution of the present utility model and do not constitute an admission that the above contents are prior art. Utility Model Content

[0005] The utility model provides a driving circuit and a power supply module of a DC / DC converter, aiming to improve the power density of the DC / DC converter in a low-power manner.

[0006] To achieve the above-mentioned purpose, the utility model proposes a driving circuit of a DC / DC converter, comprising: a first power supply end, a square wave generating unit, a first trigger, a second trigger and two driving units, wherein the first power supply end is electrically connected to the power supply ends of the square wave generating unit, the first trigger and the second trigger respectively, the signal output end of the square wave generating unit is electrically connected to the clock end of the first trigger; the signal output end of the first trigger is electrically connected to the clock end of the second trigger; the two signal output ends of the second trigger are electrically connected to the input ends of the two driving units respectively; the same-frequency signal output ends with a phase difference between the two driving units are respectively used to connect the control ends of the corresponding switch tubes in a plurality of DC / DC converters staggered in parallel.

[0007] Optionally, the square wave generating unit includes a first resistor, a second resistor, a first capacitor and a timer; wherein, the power supply end of the timer is electrically connected to the first power supply end, the first resistor is externally connected between the power supply end and the discharge end of the timer, the discharge end is also respectively connected to the threshold pin and the trigger end of the timer via the external second resistor, and the trigger end is also grounded via the first capacitor; the signal output end of the timer is the signal output end of the square wave generating unit.

[0008] Optionally, the square wave generating unit also includes a third resistor, a second capacitor and a third capacitor; wherein the third resistor is externally connected between the power supply terminal and the reset terminal of the timer, and the reset terminal is also connected to the reset signal input terminal; the common pin of the timer is also grounded via the second capacitor; and the power supply terminal of the timer is also grounded via the third capacitor.

[0009] Optionally, the power supply terminals of the first trigger and the second trigger are also grounded via a fourth capacitor.

[0010] Optionally, the driving unit includes a fourth resistor, a fifth resistor, a first diode, a second diode, a fifth capacitor, a sixth capacitor and a driver; each signal output end of the second trigger includes a forward output end and a reverse output end;

[0011] Among them, the fourth resistor and the first diode are arranged in parallel between the forward output terminal of the second trigger and the forward input terminal of the driver, and the conduction direction of the first diode is from the forward input terminal of the driver to the forward output terminal of the second trigger; the fifth resistor and the second diode are arranged in parallel between the reverse output terminal of the second trigger and the reverse input terminal of the driver, and the conduction direction of the second diode is from the reverse input terminal of the driver to the reverse output terminal of the second trigger;

[0012] The positive input terminal of the driver is also grounded via a fifth capacitor, and the negative input terminal of the driver is also grounded via a sixth capacitor.

[0013] Optionally, the power supply end of the driver is also grounded via a seventh capacitor, and the power supply end of the driver is electrically connected to the second power supply end;

[0014] The DC voltage input to the second power supply end is greater than the DC voltage input to the first power supply end.

[0015] To achieve the above-mentioned purpose, the utility model proposes a power supply module, which includes a converter circuit and a driving circuit of the DC / DC converter as described above; wherein the converter circuit is provided with a plurality of DC / DC converters staggered in parallel; the driving circuit has a plurality of same-frequency signal output terminals with phase differences, which are respectively used to connect to the control terminals of corresponding switching tubes in different DC / DC converters.

[0016] The beneficial effect of the technical solution of the utility model is that: phase interleaving control driving is realized between multiple DC / DC converters connected in parallel, and these DC / DC converters are ensured to operate at the same switching frequency and their conduction times are staggered by a certain time, so as to achieve power density improvement while effectively reducing the total ripple current and voltage, so as to reduce the control loss of the switch tube in the DC / DC converter, and achieve the purpose of improving the power density of the DC / DC converter in a low-power manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of an embodiment of a driving circuit of a DC / DC converter of the utility model;

[0018] Figure 2 It is a structural schematic diagram of another embodiment of the driving circuit of the DC / DC converter of the utility model;

[0019] Figure 3 The figure is a schematic diagram of the structure of a driving unit in a driving circuit of a DC / DC converter of the utility model.

[0020] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the scheme in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0023] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0024] In addition, if the description of "first", "second", etc. is involved in the utility model, it is only used for descriptive purposes (such as for distinguishing the same or similar elements), and cannot be understood as indicating or implying its relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0025] The utility model proposes a driving circuit of a DC / DC converter, referring to Figure 1 The driving circuit of the DC / DC converter includes a first power supply end, a square wave generating unit, a first trigger, a second trigger and two driving units, wherein the first power supply end is electrically connected to the power supply ends of the square wave generating unit, the first trigger and the second trigger respectively, the signal output end of the square wave generating unit is electrically connected to the clock end of the first trigger; the signal output end of the first trigger is electrically connected to the clock end of the second trigger; the two signal output ends of the second trigger are electrically connected to the input ends of the two driving units respectively; the same-frequency signal output ends with a phase difference between the two driving units are respectively used to connect the control ends of the corresponding switch tubes in a plurality of DC / DC converters staggered in parallel to realize a multi-level topology structure.

[0026] In this embodiment, the first power supply end is responsible for providing the required electrical energy for the normal operation of the driving circuit, and can be selected as a 5V DC input.

[0027] Optionally, the square wave generating unit may be constructed based on a timer oscillation circuit to generate a square wave signal of a specific frequency (eg, 1 MHz) and transmit it to the first trigger.

[0028] Optionally, the first trigger and the second trigger are both D-type triggers, and the D-type trigger can use a SN74HC74PWT chip.

[0029] Optionally, the first trigger is used to convert the received square wave signal into a set of two-way frequency-divided pulse signals with a phase stagger of 180°, and then transmit it to the second trigger. The second trigger is used to convert the received set of two-way frequency-divided pulse signals with a phase stagger of 180° into two sets of two-way frequency-divided pulse signals with a phase stagger of 90°, and then transmit the converted two sets of signals to the two drive units respectively (that is, each drive unit will receive a set of two-way frequency-divided pulse signals with a phase stagger of 90°).

[0030] Optionally, an RC circuit and a driver can be set in the driving unit, and the threshold voltage of the driver is used to create a dead zone through the charge and discharge time of the RC circuit, so that the generated driving signal can maintain the same frequency and a phase difference of 90°, forming a phase-staggered working mode. That is, the driving unit first filters a set of two-frequency pulse signals with a phase stagger of 90° (phase complementary 180°) received by the RC circuit, and then adjusts the dead time set by the time constant of the RC circuit (such as setting the dead time to 300ns), so that the driver can convert the set of two-frequency pulse signals after RC filtering into a set of driving signals with a phase complementary 180° with a dead time, and finally the driver outputs the finally generated driving signal to the corresponding DC / DC converter. In this way, not only the signals output by different driving units are of the same frequency and staggered phase (that is, with a phase difference), but also the signals output by the same driving unit are of the same frequency and staggered phase, forming a same-frequency signal output terminal with a phase difference.

[0031] Among them, the driving signal output by the driving unit is applied to multiple DC / DC converters connected in parallel, that is, the signal output end of each driving unit is used to electrically connect the control end of the corresponding switch tube in these DC / DC converters, so as to stagger the operation phases of multiple DC / DC converters, which can significantly reduce the ripple of input and output currents. Phase interleaving can reduce the current peak value drawn from the input source at the same time, thereby reducing the voltage drop on the input filter capacitor, and thus improving the efficiency of the system.

[0032] Optionally, taking the case where the corresponding switch tube in the DC / DC converter is a MOS tube as an example, the control end is the gate of the MOS tube.

[0033] By using multiple DC / DC converters in parallel, the total power output of the system can be increased without sacrificing output quality. This configuration allows each DC / DC converter to operate with a smaller size and weight, thereby improving the power density overall.

[0034] It should be noted that in the converter circuit, when multiple DC / DC converters are staggered in parallel, the adopted topology structure may be Buck, Boost, Buck-Boost, etc., which can be selected according to the specific application scenario and power requirements. That is, the converter circuit may adopt the existing multiple staggered parallel DC / DC converter structure (such as the staggered parallel DC / DC converter structure disclosed in patent document CN114142728A), and each signal output end of each driving unit in the driving circuit may be connected to the control end of the corresponding switch tube of each DC / DC converter (such as the gate of the MOS tube).

[0035] In one embodiment, phase staggered control driving is implemented between multiple DC / DC converters that are staggered in parallel, and it is ensured that these DC / DC converters operate at the same switching frequency and their on-times are staggered by a certain period of time, so that the power density can be improved while the total ripple current and voltage can be effectively reduced to reduce the control loss of the switch tube in the DC / DC converter, thereby achieving the purpose of improving the power density of the DC / DC converter in a low-power manner.

[0036] In one embodiment, based on the above embodiment, referring to Figure 2 The square wave generating unit comprises a first resistor R1, a second resistor R2, a first capacitor C1 and a timer; wherein the power supply terminal VCC of the timer is electrically connected to the first power supply terminal, the first resistor R1 is externally connected between the power supply terminal VCC and the discharge terminal DIS of the timer, the discharge terminal DIS is also connected to the threshold pin TH and the trigger terminal TR of the timer respectively through the external second resistor R2, and the trigger terminal TR is also grounded through the first capacitor C1; the signal output terminal OUT of the timer is the signal output terminal of the square wave generating unit.

[0037] In this embodiment, the first resistor R1 is connected between the power supply terminal VCC and the discharge terminal DIS of the timer, one end of the second resistor R2 is connected to the first resistor R1 and the discharge terminal DIS, and the other end is connected to the threshold pin TH and the trigger terminal TR of the timer (equivalent to the threshold pin TH and the trigger terminal TR being short-circuited). The first capacitor C1 is connected between the trigger terminal TR of the timer and the ground line GND.

[0038] Assuming that the DC voltage provided by the first power supply end is U, when the square wave generating unit is working, the first capacitor C1 is charged to 2 / 3U through the first resistor R1 and the second resistor R2, and then the output voltage is reversed, and the first capacitor C1 is discharged to 1 / 3U through the second resistor R2. Thereafter, the first capacitor C1 is repeatedly recharged until it reaches 2 / 3U, and the output voltage is reversed again, and so on and so forth, so that the timer can have the conditions to generate a square wave signal of a specific frequency.

[0039] The signal output terminal OUT of the timer is the signal output terminal of the square wave generating unit, and the signal output terminal OUT of the timer is electrically connected to the clock terminal CK of the first trigger to output a corresponding square wave signal to the first trigger.

[0040] In one embodiment, based on the above embodiment, referring to Figure 2The square wave generating unit further includes a third resistor R3, a second capacitor C2 and a third capacitor C3; wherein the third resistor R3 is externally connected between the power supply terminal VCC and the reset terminal RE of the timer, and the reset terminal RE is also connected to the reset signal input terminal RST; the common pin CON of the timer is also grounded via the second capacitor C2; the power supply terminal VCC of the timer is also grounded via the third capacitor C3.

[0041] In this embodiment, the third resistor R3 and the reset signal input terminal RST are used to implement the reset function of the timer. When the reset signal input terminal RST receives the reset signal, the third resistor R3 controls the reset terminal RE of the timer to remain in the reset state. In the reset state, the timer will be forced to restart, thereby ensuring that the square wave generating unit restarts timing after receiving the reset signal, so as to ensure that the system can accurately reset the state of the square wave signal when needed.

[0042] The presence of the reset function improves the stability and reliability of the system, and plays a key role, especially when it is necessary to respond to external events in a timely manner and reinitialize the square wave generation unit.

[0043] Optionally, the second capacitor C2 is connected between the common pin CON of the timer and the ground line GND, and is used to filter and stabilize the timer.

[0044] Optionally, a third capacitor C3 is connected between the power supply terminal VCC and the ground line GND of the timer to stabilize the input power supply and filter.

[0045] In one embodiment, based on the above embodiment, referring to Figure 2 The power supply terminal VCC of the first trigger and the second trigger is also grounded via a fourth capacitor C4.

[0046] In this embodiment, the power supply terminals VCC of the first trigger and the second trigger are connected to the ground line GND via the fourth capacitor C4, which helps to improve the trigger's resistance to power supply interference and enhances the stability and reliability of the trigger.

[0047] The signal output terminal OUT of the first trigger is electrically connected to the clock terminal CK of the second trigger, so as to output a set of two-frequency divided pulse signals with phases staggered by 180° to the second trigger.

[0048] In one embodiment, based on the above embodiment, referring to Figure 2 and Figure 3 , the driving unit includes a fourth resistor R4, a fifth resistor R5, a first diode D1, a second diode D2, a fifth capacitor C5, a sixth capacitor C6 and a driver; each signal output terminal OUT of the second trigger includes a forward output terminal OUT+ and a reverse output terminal OUT-;

[0049] Among them, the fourth resistor R4 and the first diode D1 are arranged in parallel between the forward output terminal OUT+ of the second trigger and the forward input terminal IN+ of the driver, and the conduction direction of the first diode D1 is from the forward input terminal IN+ of the driver to the forward output terminal OUT+ of the second trigger (that is, the anode of the first diode D1 is connected to the forward input terminal IN+ of the driver, and the cathode is connected to the forward output terminal OUT+ of the second trigger); the fifth resistor R5 and the second diode D2 are arranged in parallel between the reverse output terminal OUT- of the second trigger and the reverse input terminal IN- of the driver, and the conduction direction of the second diode D2 is from the reverse input terminal IN- of the driver to the reverse output terminal OUT- of the second trigger (that is, the anode of the second diode D2 is connected to the reverse input terminal IN- of the driver, and the cathode is connected to the reverse output terminal OUT- of the second trigger);

[0050] The positive input terminal IN+ of the driver is further connected to the ground line GND via a fifth capacitor C5, and the negative input terminal IN- of the driver is further connected to the ground line GND via a sixth capacitor C6.

[0051] In this embodiment, the two signal output terminals OUT of the second trigger are respectively connected to the corresponding driving units, and each outputs a set of two-frequency divided pulse signals with a phase staggered by 90°. Each signal output terminal OUT of the second trigger includes a forward output terminal OUT+ and a reverse output terminal OUT-, and the forward output terminal OUT+ and the reverse output terminal OUT- are connected to the same driving unit, and two signals in a set of two-frequency divided pulse signals with a phase staggered by 90° are respectively output to a driving unit through the forward output terminal OUT+ and the reverse output terminal OUT-.

[0052] Optionally, the fourth resistor R4, the first diode D1 and the fifth capacitor C5 constitute an RC circuit used by the positive input terminal IN+ of the driver; the fifth resistor R5, the second diode D2 and the sixth capacitor C6 constitute an RC circuit used by the reverse input terminal IN- of the driver.

[0053] Optionally, the driver has two signal output terminals OUT, which are used to respectively output two signals of a set of driving signals with dead time and complementary phases of 180° that are finally generated.

[0054] Optionally, the device selection of the driver may be UCC27524ADGN.

[0055] In one embodiment, based on the above embodiment, referring to Figure 3 , the power supply terminal VCC of the driver is also grounded via the seventh capacitor C7, and the power supply terminal VCC of the driver is electrically connected to the second power supply terminal;

[0056] The DC voltage input to the second power supply end is greater than the DC voltage input to the first power supply end.

[0057] In this embodiment, the second power supply terminal is connected to the power supply terminal VCC of the driver to provide sufficient working voltage for the driver. The DC voltage (optionally 12V) input to the second power supply terminal is greater than the DC voltage input to the first power supply terminal.

[0058] Optionally, the power supply terminal VCC of the driver is further connected to the ground line GND via a seventh capacitor C7 to further improve the stability and anti-interference capability of the circuit.

[0059] The utility model further proposes a power supply module, which includes a converter circuit and a driving circuit of a DC / DC converter. The specific structure of the driving circuit refers to the above-mentioned embodiment. Since the power supply module adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the technical effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0060] The converter circuit is provided with a plurality of DC / DC converters connected in parallel in an interlaced manner; the drive circuit has a plurality of same-frequency signal output terminals with phase differences, which are respectively used to connect to the control terminals of corresponding switch tubes in different DC / DC converters.

[0061] Optionally, in a converter circuit, when multiple DC / DC converters are staggered in parallel, the adopted topology may be Buck, Boost, Buck-Boost, etc., which can be selected according to the specific application scenario and power requirements. As long as the converter circuit has multiple DC / DC converters staggered in parallel, and the DC / DC converters are controlled by corresponding switch tubes (such as MOS tubes), a power module can be formed based on the drive circuit provided in the above embodiment and the converter circuit.

[0062] The above description is only a partial or preferred embodiment of the present invention. Neither the text nor the drawings can limit the scope of protection of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the overall concept of the present invention, or direct / indirect application in other related technical fields are included in the scope of protection of the present invention.

Claims

1. A driving circuit of a DC / DC converter, characterized in that: include: A first power supply end, a square wave generating unit, a first trigger, a second trigger and two driving units, wherein the first power supply end is electrically connected to the power supply ends of the square wave generating unit, the first trigger and the second trigger respectively, the signal output end of the square wave generating unit is electrically connected to the clock end of the first trigger; the signal output end of the first trigger is electrically connected to the clock end of the second trigger; The two signal output ends of the second trigger are electrically connected to the input ends of the two driving units respectively; the same-frequency signal output ends with a phase difference between the two driving units are respectively used to connect to the control ends of the corresponding switch tubes in multiple DC / DC converters staggered in parallel.

2. The driving circuit of the DC / DC converter according to claim 1, characterized in that: The square wave generating unit comprises a first resistor, a second resistor, a first capacitor and a timer; wherein the power supply end of the timer is electrically connected to the first power supply end, the first resistor is externally connected between the power supply end and the discharge end of the timer, the discharge end is also connected to the threshold pin and the trigger end of the timer respectively via the external second resistor, and the trigger end is also grounded via the first capacitor; the signal output end of the timer is the signal output end of the square wave generating unit.

3. The driving circuit of the DC / DC converter according to claim 2, characterized in that: The square wave generating unit also includes a third resistor, a second capacitor and a third capacitor; wherein the third resistor is externally connected between the power supply terminal and the reset terminal of the timer, and the reset terminal is also connected to the reset signal input terminal; the common pin of the timer is also grounded via the second capacitor; and the power supply terminal of the timer is also grounded via the third capacitor.

4. The driving circuit of the DC / DC converter according to claim 1, characterized in that: The power supply terminals of the first trigger and the second trigger are also grounded via a fourth capacitor.

5. The driving circuit of the DC / DC converter according to claim 1, characterized in that: The driving unit includes a fourth resistor, a fifth resistor, a first diode, a second diode, a fifth capacitor, a sixth capacitor and a driver; each signal output end of the second trigger includes a forward output end and a reverse output end; Among them, the fourth resistor and the first diode are arranged in parallel between the forward output terminal of the second trigger and the forward input terminal of the driver, and the conduction direction of the first diode is from the forward input terminal of the driver to the forward output terminal of the second trigger; the fifth resistor and the second diode are arranged in parallel between the reverse output terminal of the second trigger and the reverse input terminal of the driver, and the conduction direction of the second diode is from the reverse input terminal of the driver to the reverse output terminal of the second trigger; The positive input terminal of the driver is also grounded via a fifth capacitor, and the negative input terminal of the driver is also grounded via a sixth capacitor.

6. The driving circuit of the DC / DC converter according to claim 5, characterized in that: The power supply end of the driver is also grounded via a seventh capacitor, and the power supply end of the driver is electrically connected to the second power supply end; The DC voltage input to the second power supply end is greater than the DC voltage input to the first power supply end.

7. A power module, characterized in that: It comprises a converter circuit and a driving circuit of a DC / DC converter as described in any one of claims 1 to 6; wherein the converter circuit is provided with a plurality of DC / DC converters staggered in parallel; the driving circuit has a plurality of same-frequency signal output terminals with phase differences, which are respectively used to connect to the control terminals of corresponding switching tubes in different DC / DC converters.

Images