DC / DC module power supply

Abstract

The DC / DC module power supply comprises an input filter circuit, a power conversion circuit, a control circuit, an output rectification filter circuit, a feedback circuit and an auxiliary power supply circuit, the input filter circuit is connected with the power conversion circuit and the control circuit; the power conversion circuit is connected with the output rectification filter circuit, the auxiliary power supply circuit and the control circuit; the control circuit is connected with the auxiliary power supply circuit and the feedback circuit; the output rectification filter circuit is connected with the feedback circuit. According to the scheme, the structure is simple, the design is small and exquisite, and power supply conversion with a wide input voltage range, high efficiency and high stability is realized in an ultra-small volume.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and in particular to a DC / DC module power supply. Background Technology

[0002] Modular power supplies are widely used in industrial control computers, instrumentation, communication equipment, medical electronics, automotive electronics, and aerospace due to their advantages such as short design cycles, high reliability, and ease of system upgrades. In recent years, with the rapid development of data services and the widespread adoption of distributed power supply systems, the market demand for modular power supplies has grown significantly, exceeding the growth rate of traditional primary power supplies. The increasing miniaturization and portability of electronic devices places higher demands on modular power supplies, requiring higher efficiency within a smaller footprint. However, currently common ultra-miniature power supplies suffer from high cost or low conversion efficiency. Utility Model Content

[0003] An embodiment of this application provides a DC / DC module power supply.

[0004] To achieve the above objectives, embodiments of this application provide a DC / DC module power supply, including: an input filter circuit, a power conversion circuit, a control circuit, an output rectifier filter circuit, a feedback circuit, and an auxiliary power supply circuit;

[0005] The input filter circuit is connected to the power conversion circuit and the control circuit;

[0006] The power conversion circuit is connected to the output rectifier and filter circuit, auxiliary power supply circuit, and control circuit.

[0007] The control circuit is connected to the auxiliary power supply circuit and the feedback circuit;

[0008] The output rectifier and filter circuit is connected to the feedback circuit.

[0009] In one embodiment, the power conversion circuit includes an RCD snubber circuit and a power transformer connected to each other.

[0010] The RCD absorption circuit is connected to the input filter circuit and the control circuit.

[0011] The power transformer is connected to the output rectifier and filter circuit and the auxiliary power supply circuit.

[0012] In one embodiment, the power transformer includes a primary winding a, a secondary winding c, and an auxiliary winding b;

[0013] The primary winding a is connected in parallel with the RCD snubber circuit, and the opposite-named terminal of the primary winding a is connected to the control circuit.

[0014] The secondary winding C is connected in parallel with the output rectifier and filter circuit;

[0015] The auxiliary winding b is coupled to the auxiliary power supply circuit.

[0016] In one embodiment, the RCD absorption circuit includes: a fourth absorption resistor R4, a second absorption capacitor C2, and a first absorption diode D1;

[0017] One end of the fourth absorption resistor R4 is connected to one end of the second absorption capacitor C2, the input filter circuit, the control circuit, and the same-named end of the primary winding a;

[0018] The other end of the fourth absorption resistor R4 is connected to the other end of the second absorption capacitor C2 and the negative terminal of the first absorption diode D1; the positive terminal of the first absorption diode D1 is connected to the opposite terminal of the primary winding a and the control circuit.

[0019] In one embodiment, the control circuit includes: a PWM controller U3;

[0020] Pin 1 of the PWM controller U3 is connected to one end of the first voltage divider resistor R1 and one end of the second voltage divider resistor R2. The other end of the first voltage divider resistor R1 and the other end of the second voltage divider resistor R2 are connected to the input filter circuit.

[0021] Pin 2 of the PWM controller U3 is the power ground;

[0022] Pin 3 of the PWM controller U3 is connected to one end of the third current-limiting resistor R3, and the other end of the third current-limiting resistor R3 is connected to the input filter circuit and the RCD snubber circuit.

[0023] Pin 4 of the PWM controller U3 is connected to the power conversion circuit;

[0024] Pin 5 of the PWM controller U3 is connected to the feedback circuit;

[0025] Pin 6 of the PWM controller U3 is connected to the auxiliary power supply circuit and one end of the third capacitor C3, while the other end of the third capacitor C3 is grounded.

[0026] In one embodiment, the output rectifier filter circuit includes: a rectifier diode group, a fourth filter capacitor C4, and a fifth filter capacitor C5;

[0027] One end of the rectifier diode group is connected to the opposite end of the secondary winding C; the other end of the rectifier diode group is connected to one end of the fourth filter capacitor C4, one end of the fifth filter capacitor C5, and the feedback circuit.

[0028] The other end of the fourth filter capacitor C4 and the other end of the fifth filter capacitor C5 are connected to the corresponding terminals of the secondary winding C.

[0029] In one embodiment, the rectifier diode group includes a third rectifier diode D3 and a fourth rectifier diode D4 arranged in parallel;

[0030] The positive terminals of the third rectifier diode D3 and the fourth rectifier diode D4 are connected to the opposite terminals of the secondary winding C; the negative terminals of the third rectifier diode D3 and the fourth rectifier diode D4 are connected to one end of the fourth filter capacitor C4.

[0031] In one embodiment, the feedback circuit includes a voltage reference chip U1 and an optocoupler U2;

[0032] A seventh resistor R7 is connected between pins 1 and 3 of the voltage reference chip U1;

[0033] Pin 1 of the voltage reference chip U1 is connected to one end of the sixth resistor R6 and one end of the sixth capacitor C6, and the other end of the sixth resistor R6 is connected to the output rectifier and filter circuit.

[0034] Pin 2 of voltage reference chip U1 is connected to one end of the ninth resistor R9, one end of the tenth resistor R10, and pin 2 of optocoupler U2; the other end of the tenth resistor R10 is connected to the other end of the sixth capacitor C6; the other end of the ninth resistor R9 is connected to the other end of the sixth resistor R6 and one end of the eighth resistor R8; the other end of the eighth resistor R8 is connected to pin 1 of optocoupler U2; pin 4 of optocoupler U2 is connected to the control circuit; pin 3 of optocoupler U2 is grounded.

[0035] Pin 3 of the voltage reference chip U1 is grounded.

[0036] In one embodiment, the auxiliary power supply circuit includes a second rectifier diode D2;

[0037] The positive terminal of the second rectifier diode D2 is connected to one end of the fifth current-limiting resistor R5, and the other end of the fifth current-limiting resistor R5 is connected to the opposite terminal of the auxiliary winding b; the negative terminal of the second rectifier diode D2 is connected to the control circuit.

[0038] Compared with the prior art, this application has the following advantages: the power supply structure of this module is simple and compact, and it achieves power conversion with a wide input voltage range, high efficiency and high stability in an ultra-small volume. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the structure of the DC / DC module power supply according to an embodiment of this application;

[0041] Figure 2 This is a schematic diagram of the DC / DC module power supply according to an embodiment of this application;

[0042] Figure 3 This is a schematic diagram of the power transformer in the DC / DC module power supply of this application embodiment;

[0043] Figure 4 This is a top view of the power transformer in the DC / DC module power supply of this application embodiment;

[0044] Figure 5 This is a bottom view of the power transformer in the DC / DC module power supply of this application embodiment. Detailed Implementation

[0045] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0046] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0047] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation", "connection" and "joining" should be interpreted broadly, for example, they can refer to fixed connection, detachable connection, or integral connection; for those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0048] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0049] Reference Figure 1 , Figure 2 Embodiments of this application provide a DC / DC module power supply, including:

[0050] Input filter circuit 10, power conversion circuit 20, control circuit 30, output rectifier filter circuit 40, feedback circuit 50 and auxiliary power supply circuit 60;

[0051] The input filter circuit 10 is connected to the power conversion circuit 20 and the control circuit 30;

[0052] The power conversion circuit 20 is connected to the output rectifier and filter circuit 40, the auxiliary power supply circuit 60, and the control circuit 30.

[0053] The control circuit 30 is connected to the auxiliary power supply circuit 60 and the feedback circuit 50;

[0054] The output rectifier and filter circuit 40 is connected to the feedback circuit 50.

[0055] Specifically, the input filter circuit 10 is used to filter out noise from the front-end DC power supply. The input filter circuit 10 can be implemented using filter capacitors, such as... Figure 2 The first filter capacitor C1.

[0056] In one embodiment, the power conversion circuit 20 includes an RCD snubber circuit and a power transformer connected to each other;

[0057] The RCD absorption circuit is connected to the input filter circuit 10 and the control circuit 30.

[0058] The power transformer is connected to the output rectifier and filter circuit 40 and the auxiliary power supply circuit 60.

[0059] In one embodiment, such as Figure 3 , Figure 4 , Figure 5 As shown, the power transformer includes a primary winding a, a secondary winding c, and an auxiliary winding b, used to achieve voltage conversion. The transformer core e is a manganese-zinc ferrite core. There are two cores e in a set, symmetrically arranged on both sides of the frame. This core is a P7 core, which has excellent characteristics of high permeability and low loss, and can meet the low loss requirements of the transformer.

[0060] Continue to refer to Figure 2 The primary winding a is connected in parallel with the RCD absorption circuit, and the opposite-named terminal of the primary winding a is connected to the control circuit 30.

[0061] The secondary winding C is connected in parallel with the output rectifier and filter circuit 40;

[0062] The auxiliary winding b is coupled to the auxiliary power supply circuit 60.

[0063] In one embodiment, the RCD absorption circuit includes: a fourth absorption resistor R4, a second absorption capacitor C2, and a first absorption diode D1;

[0064] One end of the fourth absorption resistor R4 is connected to one end of the second absorption capacitor C2, the input filter circuit 10, the control circuit 30, and the same-named end of the primary winding a.

[0065] The other end of the fourth absorption resistor R4 is connected to the other end of the second absorption capacitor C2 and the negative terminal of the first absorption diode D1; the positive terminal of the first absorption diode D1 is connected to the opposite terminal of the primary winding a and the control circuit 30.

[0066] RCD snubber circuits are used to absorb leakage inductance energy from power transformers and suppress voltage spikes in switching transistors.

[0067] This power conversion circuit adopts a flyback topology.

[0068] In one embodiment, the control circuit 30 includes: a PWM controller U3;

[0069] Pin 1 of the PWM controller U3 is connected to one end of the first voltage divider resistor R1 and one end of the second voltage divider resistor R2. The other end of the first voltage divider resistor R1 and the other end of the second voltage divider resistor R2 are connected to the input filter circuit 10. The over- and under-voltage protection points can be adjusted by adjusting the two voltage divider resistors.

[0070] Pin 2 of the PWM controller U3 is the power ground and also the source of the built-in MOSFET.

[0071] Pin 3 of the PWM controller U3 is connected to one end of the third current-limiting resistor R3, and the other end of the third current-limiting resistor R3 is connected to the input filter circuit 10 and the RCD snubber circuit for the first start-up of the PWM controller U3.

[0072] Pin 4 of the PWM controller U3 is connected to the power conversion circuit 20. Specifically, pin 4 of the PWM controller U3 is connected to both the RCD snubber circuit and the power transformer in the power conversion circuit 20. Pin 4 of the PWM controller U3 is the drain of the built-in MOSFET. The RCD snubber circuit is connected to pin 4 of the PWM controller U3, which can absorb the leakage inductance caused by poor transformer coupling, protect the drain and source of the built-in MOSFET from breakdown, and suppress the voltage spikes generated by the high-frequency switching of the built-in MOSFET.

[0073] Pin 5 of the PWM controller U3 is connected to the feedback circuit 50. Pin 5 of the PWM controller U3 is an optocoupler feedback pin. It is isolated from the optocoupler in the feedback circuit 50 to obtain an error signal, thereby stabilizing the output voltage.

[0074] Pin 6 of the PWM controller U3 is connected to the auxiliary power supply circuit 60 and one end of the third capacitor C3, while the other end of the third capacitor C3 is grounded. Pin 6 of the PWM controller U3 is the power supply pin, connected to the auxiliary power supply circuit 60. After the PWM controller U3 is initially started, it obtains the voltage required for normal operation through coupling with the power transformer.

[0075] Specifically, the control circuit 30 is used to implement input over / under voltage protection and output voltage regulation.

[0076] For example, the PWM controller U3 can be a small-package power management chip, model VPS2109.

[0077] In one embodiment, the output rectifier filter circuit 40 includes: a rectifier diode group, a fourth filter capacitor C4, and a fifth filter capacitor C5;

[0078] One end of the rectifier diode group is connected to the opposite end of the secondary winding C; the other end of the rectifier diode group is connected to one end of the fourth filter capacitor C4, one end of the fifth filter capacitor C5, and the feedback circuit 50.

[0079] The other end of the fourth filter capacitor C4 and the other end of the fifth filter capacitor C5 are connected to the corresponding terminals of the secondary winding C.

[0080] The rectifier diode group includes a third rectifier diode D3 and a fourth rectifier diode D4 arranged in parallel.

[0081] The positive terminals of the third rectifier diode D3 and the fourth rectifier diode D4 are connected to the opposite terminals of the secondary winding C; the negative terminals of the third rectifier diode D3 and the fourth rectifier diode D4 are connected to one end of the fourth filter capacitor C4.

[0082] Specifically, the output rectifier and filter circuit 40 is used to convert the AC voltage after the power transformer into DC voltage. The rectifier diode group adopts a parallel connection of two rectifier diodes to reduce circuit loss and improve efficiency. The filter capacitor is used to smooth the output voltage and reduce AC ripple noise.

[0083] In one embodiment, the feedback circuit 50 includes a voltage reference chip U1 and an optocoupler U2;

[0084] A seventh resistor R7 is connected between pins 1 and 3 of the voltage reference chip U1;

[0085] Pin 1 of the voltage reference chip U1 is connected to one end of the sixth resistor R6 and one end of the sixth capacitor C6, and the other end of the sixth resistor R6 is connected to the output rectifier and filter circuit 40.

[0086] Pin 2 of voltage reference chip U1 is connected to one end of the ninth resistor R9, one end of the tenth resistor R10, and pin 2 of optocoupler U2; the other end of the tenth resistor R10 is connected to the other end of the sixth capacitor C6; the other end of the ninth resistor R9 is connected to the other end of the sixth resistor R6 and one end of the eighth resistor R8; the other end of the eighth resistor R8 is connected to pin 1 of optocoupler U2; pin 4 of optocoupler U2 is connected to control circuit 30; pin 3 of optocoupler U2 is grounded.

[0087] Pin 3 of the voltage reference chip U1 is grounded.

[0088] Specifically, the feedback circuit 50 compares the output voltage with the reference voltage, and transmits the difference to the control circuit 30 via optocoupler U2 to stabilize the output voltage. The feedback circuit 50 is connected to the output filter circuit and the control circuit 30. The feedback circuit 50 compares the filtered output voltage with the reference voltage of the voltage reference chip U1, and transmits the amplified difference to the PWM controller U3 via optocoupler U2 for optical isolation, thereby correcting the output voltage.

[0089] In one embodiment, the auxiliary power supply circuit 60 includes a second rectifier diode D2;

[0090] The positive terminal of the second rectifier diode D2 is connected to one end of the fifth current-limiting resistor R5, and the other end of the fifth current-limiting resistor R5 is connected to the opposite terminal of the auxiliary winding b; the negative terminal of the second rectifier diode D2 is connected to the control circuit 30.

[0091] Specifically, the auxiliary power supply circuit 60 is used to continuously supply power to the main control circuit.

[0092] The auxiliary power supply circuit 60 is connected to the power conversion circuit 20 and the control circuit 30. The voltage converted by the power conversion circuit 20 is continuously supplied to the PWM controller U3 in the control circuit 30 through the second rectifier diode D2 and the fifth current limiting resistor R5. The second rectifier diode D2 converts the AC voltage output by the power conversion circuit 20 into DC voltage for the power supply of the PWM controller U3. The fifth current limiting resistor R5 is used to protect the VDD pin of the PWM controller U3 to prevent damage to the PWM controller U3.

[0093] The working principle of the DC / DC module power supply provided in this embodiment is as follows: energy conversion and isolated power supply are achieved through high-frequency switching control. Its operation consists of two stages: when the PWM controller U3 drives the MOSFET to turn on, the input voltage is applied to the primary winding of the power transformer, the current rises linearly, and energy is stored in the power transformer core. At this time, the secondary-side rectifier diode group is cut off due to reverse bias. When the MOSFET turns off, the sudden change in the power transformer's magnetic field induces a forward voltage in the secondary winding, turning on the output diode and transferring the stored energy to the output terminal. After rectification and filtering, a stable DC voltage is obtained. A precision feedback circuit monitors the output voltage in real time and adjusts the PWM duty cycle to maintain voltage stability.

[0094] The DC / DC module power supply provided in this application embodiment is very small in size. For example, it can be 13mm×10mm×12mm, and it has a wide voltage input range of 4:1 of 9~36V, an output voltage of 12V, and a maximum output power of 1W.

[0095] The DC / DC power supply module provided in this application uses a small-package power management chip as the control core, combined with a flyback topology and low-power rectifier diodes, effectively improving power conversion efficiency. A feedback loop composed of a precision reference voltage chip and optocouplers enables precise control and regulation of the output voltage, ensuring stable output under different load conditions. This power supply module features a simple structure and compact design, achieving wide input voltage range, high efficiency, and high stability power conversion within an ultra-small size, making it particularly suitable for space-constrained electronic equipment applications.

[0096] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A DC / DC module power supply, characterized in that, include: Input filter circuit (10), power conversion circuit (20), control circuit (30), output rectifier filter circuit (40), feedback circuit (50) and auxiliary power supply circuit (60); The input filter circuit (10) is connected to the power conversion circuit (20) and the control circuit (30); The power conversion circuit (20) is connected to the output rectifier and filter circuit (40), the auxiliary power supply circuit (60), and the control circuit (30); The control circuit (30) is connected to the auxiliary power supply circuit (60) and the feedback circuit (50); The output rectifier filter circuit (40) is connected to the feedback circuit (50).

2. The DC / DC module power supply according to claim 1, characterized in that, The power conversion circuit (20) includes an RCD absorption circuit and a power transformer connected to each other; The RCD absorption circuit is connected to the input filter circuit (10) and the control circuit (30); The power transformer is connected to the output rectifier and filter circuit (40) and the auxiliary power supply circuit (60).

3. The DC / DC module power supply according to claim 2, characterized in that, The power transformer includes a primary winding a, a secondary winding c, and an auxiliary winding b; The primary winding a is connected in parallel with the RCD absorption circuit, and the opposite-named terminal of the primary winding a is connected to the control circuit (30). The secondary winding c is connected in parallel with the output rectifier and filter circuit (40); The auxiliary winding b is coupled to the auxiliary power supply circuit (60).

4. The DC / DC module power supply according to claim 3, characterized in that, The RCD absorption circuit includes: a fourth absorption resistor R4, a second absorption capacitor C2, and a first absorption diode D1; One end of the fourth absorption resistor R4 is connected to one end of the second absorption capacitor C2, the input filter circuit (10), the control circuit (30), and the same end of the primary winding a; The other end of the fourth absorption resistor R4 is connected to the other end of the second absorption capacitor C2 and the negative terminal of the first absorption diode D1; the positive terminal of the first absorption diode D1 is connected to the opposite terminal of the primary winding a and the control circuit (30).

5. The DC / DC module power supply according to claim 2, characterized in that, The control circuit (30) includes: a PWM controller U3; Pin 1 of the PWM controller U3 is connected to one end of the first voltage divider resistor R1 and one end of the second voltage divider resistor R2, and the other ends of the first voltage divider resistor R1 and the second voltage divider resistor R2 are connected to the input filter circuit (10). Pin 2 of the PWM controller U3 is the power ground; Pin 3 of the PWM controller U3 is connected to one end of the third current-limiting resistor R3, and the other end of the third current-limiting resistor R3 is connected to the input filter circuit (10) and the RCD absorption circuit. Pin 4 of the PWM controller U3 is connected to the power conversion circuit (20); Pin 5 of the PWM controller U3 is connected to the feedback circuit (50); Pin 6 of the PWM controller U3 is connected to the auxiliary power supply circuit (60) and one end of the third capacitor C3, and the other end of the third capacitor C3 is grounded.

6. The DC / DC module power supply according to claim 4, characterized in that, The output rectifier and filter circuit (40) includes: a rectifier diode group, a fourth filter capacitor C4 and a fifth filter capacitor C5; One end of the rectifier diode group is connected to the opposite end of the secondary winding c; the other end of the rectifier diode group is connected to one end of the fourth filter capacitor C4, one end of the fifth filter capacitor C5, and the feedback circuit (50). The other end of the fourth filter capacitor C4 and the other end of the fifth filter capacitor C5 are connected to the corresponding terminals of the secondary winding C.

7. The DC / DC module power supply according to claim 6, characterized in that, The rectifier diode group includes a third rectifier diode D3 and a fourth rectifier diode D4 arranged in parallel; The positive terminals of the third rectifier diode D3 and the fourth rectifier diode D4 are connected to the opposite terminals of the secondary winding C; the negative terminals of the third rectifier diode D3 and the fourth rectifier diode D4 are connected to one end of the fourth filter capacitor C4.

8. The DC / DC module power supply according to claim 1, characterized in that, The feedback circuit (50) includes: a voltage reference chip U1 and an optocoupler U2; A seventh resistor R7 is connected between pins 1 and 3 of the voltage reference chip U1; Pin 1 of the voltage reference chip U1 is connected to one end of the sixth resistor R6 and one end of the sixth capacitor C6, and the other end of the sixth resistor R6 is connected to the output rectifier and filter circuit (40). Pin 2 of the voltage reference chip U1 is connected to one end of the ninth resistor R9, one end of the tenth resistor R10, and pin 2 of the optocoupler U2; the other end of the tenth resistor R10 is connected to the other end of the sixth capacitor C6; the other end of the ninth resistor R9 is connected to the other end of the sixth resistor R6 and one end of the eighth resistor R8; the other end of the eighth resistor R8 is connected to pin 1 of the optocoupler U2; pin 4 of the optocoupler U2 is connected to the control circuit (30); pin 3 of the optocoupler U2 is grounded. Pin 3 of the voltage reference chip U1 is grounded.

9. The DC / DC module power supply according to claim 4, characterized in that, The auxiliary power supply circuit (60) includes a second rectifier diode D2; The positive terminal of the second rectifier diode D2 is connected to one end of the fifth current-limiting resistor R5, and the other end of the fifth current-limiting resistor R5 is connected to the opposite end of the auxiliary winding b; the negative terminal of the second rectifier diode D2 is connected to the control circuit (30).

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