Power supply circuit and power supply device

Abstract

The utility model provides a power supply circuit and a power supply device, the power supply circuit comprises a control module, a positive output module and a negative output module, the positive output module comprises a first switch tube and a second switch tube which are sequentially connected between a first power supply and the ground, and an intermediate node of the first switch tube and the second switch tube is a positive output node; the negative output module comprises a first capacitor and a second capacitor which are sequentially connected between the first power supply and the ground, and an intermediate node of the first capacitor and the second capacitor is a negative output node; the control module comprises a self-excited oscillation unit, a differential unit and a half-bridge driving unit which are connected in sequence, and is used for controlling the first switching tube and the second switching tube to be switched on alternately. The power supply circuit and the power supply device provided by the utility model can guarantee the output stability through the charging and discharging of the capacitor in the negative output module, can reduce the precision requirement on the control module, can reduce the cost of drive control hardware, and can effectively reduce the cost of a high-performance DC-to-DC switching power supply.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply, in particular to a power supply circuit and a power supply device. Background Art

[0002] DC-DC switching power supplies have a wide range of applications. For example, in industrial automation, communication base stations, medical equipment and other fields, they can provide working power for various power-consuming modules.

[0003] In the prior art, a DC-to-DC switching power supply generally converts the total DC power supply into a high-frequency AC power supply, then performs voltage conversion through a transformer, and finally obtains DC power supplies of various voltage specifications through current rectification. The voltage conversion performed by the high-frequency AC power supply ensures voltage stability and improves the voltage stability of the various DC power supplies ultimately provided. However, in the process of converting the total DC power supply into a high-frequency AC power supply, to ensure the accuracy of the output voltage, the high-frequency operation drive of the bridge circuit requires a dedicated drive control chip and a single-chip microcomputer. The combined material cost of the dedicated drive control chip and single-chip microcomputer is relatively high, which increases the cost of the DC-to-DC switching power supply. Utility Model Content

[0004] Based on this, the purpose of the present invention is to provide a power supply circuit and a power supply device to solve the problem of high cost of high-performance DC-DC switching power supplies in the prior art.

[0005] The present invention provides a power supply circuit, comprising: a control module, a positive output module and a negative output module, wherein:

[0006] The positive output module includes a first switch tube and a second switch tube connected in sequence between a first power supply and a ground, wherein an intermediate node between the first switch tube and the second switch tube is a positive output node;

[0007] The negative output module includes a first capacitor and a second capacitor connected in sequence between a first power supply and a ground, wherein an intermediate node between the first capacitor and the second capacitor is a negative output node;

[0008] The control module includes a self-excited oscillation unit, a differential unit and a half-bridge drive unit connected in sequence, the first drive output end and the second drive output end of the half-bridge drive unit are respectively connected to the control ends of the first switch tube and the second switch tube, the half-bridge drive unit includes two drive channels corresponding to the first drive output end and the second drive output end, respectively, and the two drive channels are respectively connected to the two differential output ends of the differential unit.

[0009] Optionally, the self-excited oscillation unit includes a Schmitt trigger chip, and the input resistor of the logic input end of the Schmitt trigger chip is also connected between the logic input end and the logic output end of the Schmitt trigger chip to provide a first clock signal to the differential unit at the logic output end of the Schmitt trigger chip.

[0010] Optionally, the self-oscillation unit further includes a third capacitor and a fourth capacitor, one end of the third capacitor and the fourth capacitor are grounded, and the other ends are connected to the logic input terminal and the logic output terminal respectively.

[0011] Optionally, two transmission circuits corresponding to the two driving channels are further provided between the differential unit and the half-bridge driving unit, a first resistor is connected between the input end and the output end of the transmission circuit, and a reverse diode and a second resistor are connected in parallel with the first resistor and sequentially arranged between the input end and the output end of the transmission circuit, and a fifth capacitor is connected between the output end and the ground of the transmission circuit.

[0012] Optionally, the gates of the first switching tube and the second switching tube are both connected to the output end through a resistor.

[0013] Optionally, the first switching transistor and the second switching transistor include insulated gate bipolar transistors.

[0014] Optionally, the self-excited oscillation unit includes a SN74LVC1G14DBVR Schmitt trigger chip, the differential unit includes a SN74LVC2G74DCTR D trigger chip, and the half-bridge drive unit includes an IR2101STRPBF gate driver chip.

[0015] Optionally, the transformer module includes multiple transformer output units, the transformer output unit includes a transformer and a rectifier circuit, the primary winding of the transformer is connected between the positive output node and the negative output node, and the secondary winding of the transformer is connected to the rectifier circuit.

[0016] Optionally, the voltage transformation output unit includes multiple groups of the rectifier circuits, the transformer includes multiple groups of secondary windings, and the secondary windings are connected to the rectifier circuits in a one-to-one correspondence, and the number of turns of the secondary windings is different from each other.

[0017] Another aspect of the present invention provides a power supply device, which includes the above-mentioned power supply circuit.

[0018] The power supply circuit provided by the utility model includes a control module, a positive output module, and a negative output module, wherein the positive output module includes a first switching transistor and a second switching transistor connected in sequence between a first power supply and a ground, with the intermediate node between the first switching transistor and the second switching transistor being the positive output node; the negative output module includes a first capacitor and a second capacitor connected in sequence between the first power supply and the ground, with the intermediate node between the first capacitor and the second capacitor being the negative output node; the control module includes a self-excited oscillation unit, a differential unit, and a half-bridge drive unit connected in sequence, wherein the first drive output terminal and the second drive output terminal of the half-bridge drive unit are respectively connected to the control terminals of the first switching transistor and the second switching transistor; the half-bridge drive unit includes two drive channels corresponding to the first drive output terminal and the second drive output terminal, and the two drive channels are respectively connected to the two differential output terminals of the differential unit, thereby driving the positive output module to alternately output the first power supply potential and the ground potential, and cooperates with the capacitor in the negative output module to provide a stable AC power output at the positive output node and the negative output node. The output stability of the positive and negative output modules of the power supply circuit provided by the utility model is high, which can reduce the accuracy requirements of the control module, reduce the cost of the drive control hardware, and thus effectively reduce the cost of a high-performance DC-DC switching power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the main structure of the power supply circuit in the embodiment of the present utility model;

[0020] Figure 2 This is a partial structural diagram of a power supply circuit in an embodiment of the present utility model;

[0021] Figure 3 Schematic diagram of the structure of the first power management unit of the power circuit in an embodiment of the present utility model.

[0022] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0023] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be provided below with reference to the accompanying drawings. The drawings illustrate several embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present invention.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. 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. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended only to describe specific embodiments and are not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] The invention aims to solve the problem of high cost of high performance DC-DC switching power supplies in the prior art. The utility model provides a power supply circuit, including a control module, a positive output module, and a negative output module. The positive output module includes a first switching transistor and a second switching transistor connected in sequence between a first power supply and a ground, with an intermediate node between the first switching transistor and the second switching transistor being a positive output node. The negative output module includes a first capacitor and a second capacitor connected in sequence between the first power supply and the ground, with an intermediate node between the first capacitor and the second capacitor being a negative output node. The control module includes a self-excited oscillation unit, a differential unit, and a half-bridge drive unit connected in sequence. The first drive output terminal and the second drive output terminal of the half-bridge drive unit are respectively connected to the control terminals of the first switching transistor and the second switching transistor. The half-bridge drive unit includes two drive channels corresponding to the first drive output terminal and the second drive output terminal, respectively. The two drive channels are respectively connected to the two differential output terminals of the differential unit, thereby driving the positive output module to alternately output a first power supply potential and a ground potential. In conjunction with the capacitor in the negative output module, the positive output module can provide a stable AC power output at the positive output node and the negative output node. The positive and negative output modules have high output stability, which can reduce the accuracy requirements for the control module, reduce the cost of the drive control hardware, and thus effectively reduce the cost of a high-performance DC-DC switching power supply.

[0027] Specifically, if Figure 1 and Figure 2As shown, the power supply circuit of this embodiment includes: a control module, a positive output module and a negative output module 22, wherein the positive output module includes a first switch tube Q1 and a second switch tube Q2 connected in sequence between the first power supply V1 and the ground, and the intermediate node between the first switch tube Q1 and the second switch tube Q2 is the positive output node A1; the negative output module 22 includes a first capacitor C1 and a second capacitor C2 connected in sequence between the first power supply V1 and the ground, and the intermediate node between the first capacitor C1 and the second capacitor C2 is the negative output node A2. When the first switch tube Q1 and the second switch tube Q2 are alternately turned on, an AC output can be provided between the positive output node A1 and the negative output node A2.

[0028] The negative output module 22 is provided with two first capacitors C1 and two second capacitors C2 connected in parallel, which can improve the charging and discharging stability and further improve the stability of the output voltage mode.

[0029] The control module includes a self-excited oscillation unit 11, a differential unit 12 and a half-bridge drive unit 13 connected in sequence. The first drive output end and the second drive output end of the half-bridge drive unit 13 are respectively connected to the control ends of the first switch tube Q1 and the second switch tube Q2. The half-bridge drive unit 13 includes two drive channels corresponding to the first drive output end and the second drive output end, respectively, and the two drive channels are respectively connected to the two differential output ends of the differential unit 12, so as to provide two drive signals respectively through the two drive channels according to the two clock signals that are differentiated from each other, and respectively drive the first switch tube Q1 and the second switch tube Q2, so that the first switch tube Q1 and the second switch tube Q2 are turned on alternately in time sharing.

[0030] To reduce the cost of obtaining the first clock signal, in this embodiment, the self-oscillation unit 11 includes a Schmitt trigger chip U1, and the input resistor R0 of the logic input terminal (terminal A) of the Schmitt trigger chip U1 is also connected between the logic input terminal (terminal A) and the logic output terminal (terminal Y) of the Schmitt trigger chip U1, so as to provide the first clock signal to the differential unit 12 at the logic output terminal of the Schmitt trigger chip U1. Compared to crystal oscillators, Schmitt trigger chips are less expensive, which can reduce the cost of the control module.

[0031] In order to improve the signal quality of the first clock signal, in this embodiment, the self-oscillation unit 11 further includes a third capacitor C3 and a fourth capacitor C4. One end of the third capacitor C3 and the fourth capacitor C4 is grounded, and the other end is connected to the logic input end and the logic output end respectively. The logic output end is stabilized by the fourth capacitor C4, which can improve the stability of the first clock signal and further improve the self-oscillation accuracy.

[0032] A resistor and a capacitor are connected in series between the self-excited oscillation unit 11 and the differential unit 12 to filter out DC interference and limit the clock signal current, thereby ensuring the accuracy and security of the first clock signal received by the differential unit 12 and the reliability of subsequent processing.

[0033] The Schmitt trigger chip U1 can select the SN74LVC1G14DBVR Schmitt trigger chip to meet the technical requirements.

[0034] To ensure the reliability of the differential signal provided by the differential unit 12 to the half-bridge driver unit 13, two transmission circuits corresponding to the two drive channels are provided between the differential unit 12 and the half-bridge driver unit 13. A first resistor R1 is connected between the input and output ends of the transmission circuits. A reverse diode D1 and a second resistor R2 are connected in parallel with the first resistor R1 and are sequentially arranged between the input and output ends of the transmission circuit. A fifth capacitor C5 is connected between the output ends of the transmission circuit. After differential processing by the differential unit 12, two differential second clock signals are provided and output to the half-bridge driver unit 13.

[0035] The differential unit 12 can be implemented by the SN74LVC2G74DCTR type D flip-flop chip U2, which triggers the output signal to flip according to the rising edge of the first clock signal, provides a second clock signal period that is twice the period of the first clock signal, and provides two second clock signal outputs that are inverted to each other at the D port and the Q port.

[0036] The driving voltage of the switch tube is generally high. In this embodiment, the Schmitt trigger chip U1 and the D trigger chip U2 use the second power supply V2 as the working power supply, and the half-bridge driver chip U3 uses the first power supply V1 as the working power supply. The voltage of the first power supply is greater than the voltage of the second power supply. For example, the first power supply is a 12V DC source and the second power supply is a 5V DC source. The first power supply is also used as the output power supply, and the stability requirement is relatively high. Figure 3 As shown, the first power supply is also supplied by an external power supply V10 after being stabilized by an RC filter circuit.

[0037] In this embodiment, the gates of the first and second switching transistors Q1 and Q2 are connected to the output terminal via a resistor, which serves as a current discharge path for the gate drive signal, preventing excessive gate voltage and ensuring the stability and reliability of the half-bridge drive. The half-bridge drive unit 13 can be implemented using the IR2101STRPBF gate driver chip U3.

[0038] Based on the output power requirements, the first switch tube Q1 and the second switch tube Q2 include insulated gate bipolar transistors with strong load capacity, which can meet the total power requirements of multiple output loads. The specific model can be selected according to the total load power, and this application does not impose any special restrictions on this.

[0039] According to the number of loads and the load isolation requirements for the power supply, it is generally necessary to provide multiple relatively isolated power outputs. Correspondingly, it also includes a transformer module, which includes multiple transformer output units. A single transformer output unit such as Figure 2 As shown, it includes a transformer T0 and a rectifier circuit 31. The primary winding of the transformer T0 is connected between the positive output node A1 and the negative output node A2. The secondary winding of the transformer T0 is connected to the rectifier circuit 31. After transformation and rectification, a DC power output of corresponding voltage specifications is provided.

[0040] To improve system integration, the transformer output unit includes multiple sets of rectifier circuits 31, and transformer T0 includes multiple sets of secondary windings, each connected to a rectifier circuit 31 in a one-to-one relationship. The number of turns of the secondary windings varies, reducing the number of transformers required. The specific number of transformers, the number of secondary windings, and the number of rectifier circuits 31 can be flexibly selected based on specific needs and are not specifically limited in this application.

[0041] The utility model also provides a power supply device, including the above-mentioned power supply circuit, which ensures the stability of the output voltage and can reduce the hardware cost of the high-performance DC-DC switching power supply.

[0042] The power supply circuit and power supply device provided by the utility model can ensure output stability by charging and discharging the capacitor in the negative output module, which can reduce the accuracy requirements for the control module and the cost of the drive control hardware, thereby effectively reducing the cost of a high-performance DC-DC switching power supply.

[0043] Furthermore, the control module can use a Schmitt trigger chip, a D trigger chip and a half-bridge driver chip to drive the half-bridge circuit. Compared with the dedicated drive control chip and single-chip microcomputer used in the prior art, the implementation cost of the control module can be reduced. In a specific example, the implementation cost of the control module can be reduced to one-third of the cost of the prior art. Compared with the frequency modulation based on the crystal oscillator in the prior art, the operating frequency can be simply and effectively controlled by adjusting the peripheral circuit parameters of the Schmitt trigger chip. It has strong compatibility and is particularly suitable for customized application scenarios with stable working conditions.

[0044] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0045] The above-described embodiments merely represent several specific implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A power supply circuit, characterized in that: include: control module, positive output module and negative output module, wherein, The positive output module includes a first switch tube and a second switch tube connected in sequence between a first power supply and a ground, wherein an intermediate node between the first switch tube and the second switch tube is a positive output node; The negative output module includes a first capacitor and a second capacitor connected in sequence between a first power supply and a ground, wherein an intermediate node between the first capacitor and the second capacitor is a negative output node; The control module includes a self-excited oscillation unit, a differential unit and a half-bridge drive unit connected in sequence, the first drive output end and the second drive output end of the half-bridge drive unit are respectively connected to the control ends of the first switch tube and the second switch tube, the half-bridge drive unit includes two drive channels corresponding to the first drive output end and the second drive output end, respectively, and the two drive channels are respectively connected to the two differential output ends of the differential unit.

2. The power supply circuit according to claim 1, wherein: The self-excited oscillation unit includes a Schmitt trigger chip, and the input resistor of the logic input end of the Schmitt trigger chip is also connected between the logic input end and the logic output end of the Schmitt trigger chip to provide a first clock signal to the differential unit at the logic output end of the Schmitt trigger chip.

3. The power supply circuit according to claim 2, wherein: The self-excited oscillation unit further includes a third capacitor and a fourth capacitor. One end of the third capacitor and the fourth capacitor are grounded, and the other ends are connected to the logic input terminal and the logic output terminal, respectively.

4. The power supply circuit according to claim 1, wherein: Two transmission circuits corresponding to the two drive channels are further provided between the differential unit and the half-bridge drive unit. A first resistor is connected between the input end and the output end of the transmission circuit, and a reverse diode and a second resistor are connected in parallel with the first resistor and sequentially arranged between the input end and the output end of the transmission circuit. A fifth capacitor is connected between the output end and the ground of the transmission circuit.

5. The power supply circuit according to claim 1, wherein: The gates of the first switching tube and the second switching tube are both connected to the output end through a resistor.

6. The power supply circuit according to claim 1, wherein: The first switching transistor and the second switching transistor include insulated gate bipolar transistors.

7. The power supply circuit according to claim 2, wherein: The self-excited oscillation unit includes a SN74LVC1G14DBVR Schmitt trigger chip, the differential unit includes a SN74LVC2G74DCTR D trigger chip, and the half-bridge drive unit includes an IR2101STRPBF gate driver chip.

8. The power supply circuit according to claim 1, wherein: It also includes a transformer module, which includes multiple transformer output units. The transformer output unit includes a transformer and a rectifier circuit. The primary winding of the transformer is connected between the positive output node and the negative output node, and the secondary winding of the transformer is connected to the rectifier circuit.

9. The power supply circuit according to claim 8, wherein: The voltage transformation output unit includes multiple groups of the rectifier circuits, the transformer includes multiple groups of secondary windings, and the secondary windings are connected to the rectifier circuits in a one-to-one correspondence, and the numbers of turns of the secondary windings are different from each other.

10. A power supply device, characterized in that: A power supply circuit comprising the power supply circuit according to any one of claims 1 to 9.

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