Wide-voltage output power supply circuit

Abstract

The invention discloses a wide-voltage output power supply circuit. The circuit comprises a control chip; a field effect circuit; a transformer; the field effect circuit is electrically connected with the secondary side filtering and rectifying circuit through the transformer, and the secondary side filtering and rectifying circuit is electrically connected with the common mode inductor; the circuit further comprises a voltage stabilizing circuit, a reference chip, a first advanced feedback circuit, a second advanced feedback circuit and at least one output voltage feedback circuit, the voltage stabilizing circuit and the reference chip are electrically connected with the control chip through an optocoupler switch, and the first advanced feedback circuit is connected with the voltage stabilizing circuit and the reference chip in parallel. The second advanced feedback circuit and the output voltage feedback circuit are connected in parallel and then are connected in series with the voltage stabilizing circuit, the reference chip and the first advanced feedback circuit. According to the invention, a single power supply can adapt to application scene requirements of different output voltages, the stability and reliability of the circuit can be improved through voltage feedback regulation, the voltage regulation range is enlarged, the operation is flexible and convenient, and the service life is prolonged.

Description

Technical Field

[0001] This invention relates to the field of switching power supply technology, and in particular to a wide-voltage output power supply circuit. Background Technology

[0002] In the field of power technology, power management chips are often used to adjust the input voltage to the voltage actually required by the electrical equipment. However, imported power management chips have long delivery cycles, often resulting in insufficient supply, and are also expensive. Although domestically produced chips can replace imported chips, they require the application interface of the circuit, which limits the production and processing and results in low production efficiency.

[0003] Currently, high-power (100W and above) LED strip power supplies are all single power supplies with fixed output voltages. There are few single power supplies that can freely switch between multiple voltage outputs. The reason is that the output voltage range is large. Directly using the output to power the 431 feedback chip will cause the 431 feedback chip to be insufficient in voltage withstand. Therefore, an additional transformer auxiliary winding is needed to power the 431 feedback chip, which not only increases the complexity of the circuit structure, but also makes it unstable. Summary of the Invention

[0004] The purpose of this invention is to provide a wide-voltage output power supply circuit solution to address the shortcomings of existing technologies. This solution not only enables a single power supply to adapt to different application scenarios with varying output voltages, but also improves the stability and reliability of the circuit through voltage feedback adjustment, increases the voltage regulation range, provides flexible and convenient operation, and extends the service life.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A wide-voltage output power supply circuit, comprising:

[0007] Control chip;

[0008] Field-effect circuit, the control chip is electrically connected to the field-effect circuit;

[0009] At least one transformer;

[0010] And at least one secondary-side filter rectifier circuit, the field-effect circuit is electrically connected to the secondary-side filter rectifier circuit through a transformer, and the secondary-side filter rectifier circuit is electrically connected to a common-mode inductor;

[0011] Its features are:

[0012] It also includes a voltage regulator circuit, a reference chip, a first lead feedback circuit, a second lead feedback circuit, and at least one output voltage feedback circuit. The voltage regulator circuit and the reference chip are electrically connected to the control chip via an optocoupler switch. The first lead feedback circuit is connected in parallel with the voltage regulator circuit and the reference chip. The second lead feedback circuit and the output voltage feedback circuit are connected in parallel and then connected in series with the voltage regulator circuit, the reference chip, and the first lead feedback circuit. Through the design of the above structure, not only can a single power supply adapt to the application requirements of different output voltage scenarios, but also the stability and reliability of the circuit can be improved through voltage feedback regulation, the voltage regulation range can be increased, the operation is flexible and convenient, and the service life can be extended.

[0013] Furthermore, the voltage regulator circuit includes a transistor Q10, a resistor R42, and a Zener diode DV1. The base of the transistor Q10 is connected to the resistor R42 and the Zener diode DV1, and the collector of the transistor Q10 is connected to the resistor R42, the second lead feedback circuit, and the output voltage feedback circuit. The emitter of the transistor Q10 is connected to the optocoupler switch, the reference chip, and the first lead feedback circuit, which can make the power supply of the reference chip stable and reliable.

[0014] Furthermore, the first lead feedback circuit includes a capacitor C24 and a resistor R38 connected in series. The capacitor C24 is electrically connected to the optocoupler switch, the reference chip, and the voltage regulator circuit, and the resistor R38 is electrically connected to the reference chip.

[0015] Furthermore, it also includes resistors R34 and R35 connected in parallel. The voltage regulator circuit is electrically connected to the optocoupler switch through resistor R34, and the voltage regulator circuit is electrically connected to the first advance feedback circuit, the reference chip, and the optocoupler switch through resistor R35.

[0016] Furthermore, it also includes voltage divider resistors R36 and R40. The voltage divider resistor R36 is connected in parallel with the second lead feedback circuit and the output voltage feedback circuit. The voltage divider resistor R40 is connected in parallel with the reference chip and then connected in series with the voltage divider resistor R36, the second lead feedback circuit and the output voltage feedback circuit.

[0017] Furthermore, the voltage divider resistor R40 and the reference chip are electrically connected to the voltage regulator circuit, the secondary-side filter rectifier circuit, and the common-mode inductor.

[0018] Furthermore, the second lead feedback circuit includes a capacitor C25 and a resistor R43. The capacitor C25 and the resistor R43 are connected in series and then in parallel with the output voltage feedback circuit. The second lead feedback circuit, composed of the capacitor C25 and the resistor R43, can effectively solve the problem of overcharging during startup.

[0019] Furthermore, the output voltage feedback circuit includes an adjustment switch and a resistor. The adjustment switch and the resistor are connected in series and then in parallel with the second lead feedback circuit. By adjusting the switch and the resistor with different resistance values, different output voltages can be obtained to meet the wide voltage output requirements of the power supply circuit.

[0020] Furthermore, it also includes a primary-side AC filter rectifier circuit, an RCD spike absorption circuit, and at least one RCD absorption circuit, wherein the primary-side AC filter rectifier circuit is electrically connected to the transformer through the RCD spike absorption circuit and the RCD absorption circuit.

[0021] Furthermore, it also includes an auxiliary power supply circuit, which is electrically connected to the transformer.

[0022] The present invention, by adopting the above-described technical solution, has the following beneficial effects:

[0023] This invention not only enables a single power supply to adapt to different application scenarios with varying output voltages, but also improves circuit stability and reliability through voltage feedback regulation, increases the voltage regulation range, offers flexible and convenient operation, and extends service life. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings:

[0025] Figure 1 This is a circuit diagram of a wide-voltage output power supply circuit according to the present invention. Detailed Implementation

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0029] like Figure 1 As shown, this invention provides a wide-voltage output power supply circuit, which includes a control chip, a primary-side AC filter and rectifier circuit, an RCD spike absorption circuit, at least one RCD absorption circuit, a field-effect circuit, at least one transformer, at least one secondary-side filter and rectifier circuit, and a common-mode inductor TF1.

[0030] The RCD absorption circuit in this application includes a first RCD absorption circuit and a second RCD absorption circuit connected in parallel. The transformer includes a first transformer T1 and a second transformer T3. The secondary-side filter and rectifier circuit includes a first secondary-side filter and rectifier circuit and a second secondary-side filter and rectifier circuit connected in parallel.

[0031] The RCD peak absorption circuit includes capacitor C12, resistor R17, resistor R18, and high-voltage diodes D8 and D9 connected in parallel in the same direction. After capacitor C12, resistor R17, and resistor R18 are connected in parallel, they are connected in series with the parallel high-voltage diodes D8 and D9.

[0032] The first RCD snubber circuit includes capacitor C3, resistor R5, resistor R6 and high-voltage diode D4. The capacitor C3, resistor R5 and resistor R6 are connected in parallel and then connected in series with high-voltage diode D4.

[0033] The second RCD absorption circuit includes capacitor C11, resistor R11, resistor R12 and high voltage diode D6. The capacitor C11, resistor R11 and resistor R12 are connected in parallel and then connected in series with high voltage diode D6.

[0034] The field-effect circuit includes a field-effect transistor (FET) Q2. The drain of FET Q2 is connected in parallel with a series resistor R27 and a capacitor C20. The source of FET Q2 is connected to ground (GND) through parallel resistors R30, R31, R32, and R33. Resistor R30 is connected in series with capacitor C22. The gate of FET Q2 is connected in series with parallel resistors R26 and R29. Resistor R29 is connected to the source of FET Q2. Resistor R26 is connected in series with the FlyBuck control chip. FET Q2 is preferably a MOSFET.

[0035] The auxiliary power supply circuit includes a high-voltage diode D10, a high-voltage diode D11, a polarized capacitor C23, a polarized capacitor C16, a resistor R20, a transistor Q11, and a Zener diode DV2. The polarized capacitor C23 is connected in parallel with the resistor R20 and the transistor Q11, and then connected in series with the high-voltage diode D10. The high-voltage diode D10 is electrically connected to the second transformer T3. The polarized capacitor C23 is grounded. The transistor Q11 is grounded through the Zener diode DV2. The transistor Q11 is connected in series with the polarized capacitor C16 through the high-voltage diode D11. The polarized capacitor C16 is grounded.

[0036] The first secondary-side filter rectifier circuit includes capacitor C1, resistors R3 and R8, high-voltage diodes D2 and D3, polarized capacitors C7, C8, and C9. Capacitor C1 is connected in series with resistor R3, then in parallel with the parallel-connected high-voltage diodes D2 and D3, and finally in parallel with resistors R8, C7, C8, and C9 before being connected to common-mode inductor TF1.

[0037] The second secondary-side filter rectifier circuit includes capacitor C10, capacitor CY1, resistors R9 and R21, high-voltage diodes D5 and D7, polarized capacitors C13, C14, and C15. Capacitor C10 and resistor R9 are connected in series, then in parallel with high-voltage diodes D5 and D7, and then in parallel with resistors R21, C13, C14, and C15 before connecting to common-mode inductor TF1. One end of capacitor CY1 is connected to the second transformer T3, resistor R21, polarized capacitors C13, C14, C15, and common-mode inductor TF1; the other end of capacitor CY1 is grounded.

[0038] The primary-side AC filter rectifier circuit is electrically connected to the first transformer T1 through the first RCD absorption circuit.

[0039] The primary-side AC filter rectifier circuit is electrically connected to the second transformer T3 through the RCD spike absorption circuit and the second RCD absorption circuit.

[0040] The GET pin of the FlyBuck control chip is electrically connected to the field-effect circuit, which is electrically connected to the RCD spike absorption circuit, the second RCD absorption circuit, and the second transformer T3.

[0041] The field-effect circuit is electrically connected to the second secondary-side filter and rectifier circuit through the second transformer T3. The first secondary-side filter and rectifier circuit and the second secondary-side filter and rectifier circuit are electrically connected to the common-mode inductor TF1.

[0042] The wide-voltage output power supply circuit also includes an auxiliary power supply circuit, which is electrically connected to the second transformer T3.

[0043] The wide-voltage output power supply circuit also includes a voltage regulator circuit, a reference chip, a first lead feedback circuit, a second lead feedback circuit, and at least one output voltage feedback circuit.

[0044] The voltage regulator circuit and the reference chip are electrically connected to the FB pin of the control chip via an optocoupler switch PC1. The voltage regulator circuit includes a transistor Q10, a resistor R42, and a Zener diode DV1. The base of the transistor Q10 is connected to the resistor R42 and the Zener diode DV1, and the collector of the transistor Q10 is connected to the resistor R42, the second lead feedback circuit, and the output voltage feedback circuit. The emitter of the transistor Q10 is connected to the optocoupler switch, the reference chip, and the first lead feedback circuit, which can make the power supply of the reference chip stable and reliable.

[0045] The first lead feedback circuit is connected in parallel with the voltage regulator circuit and the reference chip. The first lead feedback circuit includes a capacitor C24 and a resistor R38 connected in series. The capacitor C24 is electrically connected to the optocoupler switch, the output pin K of the reference chip and the voltage regulator circuit, and the resistor R38 is electrically connected to the control pin R of the reference chip.

[0046] The second lead feedback circuit and the output voltage feedback circuit are connected in parallel and then in series with the voltage regulator circuit, the reference chip, and the first lead feedback circuit. The second lead feedback circuit includes a capacitor C25 and a resistor R43. The capacitor C25 and the resistor R43 are connected in series and then in parallel with the output voltage feedback circuit. The second lead feedback circuit, composed of the capacitor C25 and the resistor R43, can effectively solve the problem of overcharging during startup.

[0047] The wide-voltage output power supply circuit also includes resistors R34 and R35 connected in parallel. The voltage regulator circuit is electrically connected to the optocoupler switch through resistor R34, and the voltage regulator circuit is electrically connected to the first lead feedback circuit, the reference chip and the optocoupler switch through resistor R35.

[0048] The wide-voltage output power supply circuit also includes voltage divider resistors R36 and R40. The voltage divider resistors R36 are connected in parallel with the second lead feedback circuit and the output voltage feedback circuit. The voltage divider resistor R40 is connected in parallel with the reference chip and then connected in series with the voltage divider resistor R36, the second lead feedback circuit and the output voltage feedback circuit.

[0049] The voltage divider resistor R40 and the reference chip are electrically connected to the voltage regulator circuit, the secondary-side filter rectifier circuit, and the common-mode inductor.

[0050] The number of output voltage feedback circuits in this invention can be selected according to actual usage needs. The output voltage feedback circuit includes an adjusting switch and a resistor. The adjusting switch and resistor are connected in series and then in parallel with the second lead feedback circuit. By adjusting the switch and the resistor with different resistance values, different output voltages can be obtained, meeting the wide voltage output requirements of the power supply circuit.

[0051] The above structural design not only allows a single power supply to adapt to different output voltage application scenarios, but also improves the stability and reliability of the circuit through voltage feedback regulation, increases the voltage regulation range, makes operation flexible and convenient, and extends service life.

[0052] In actual operation, the input AC mains power is rectified into DC voltage by F1 / TF3 / TF2 / DB1 / C4 / C5. The FlyBuck control chip outputs a PWM wave with a corresponding duty cycle to drive Q2 based on the magnitude of the feedback signal FB, causing T1 / T3 to perform energy conversion accordingly. The FB signal is sampled by the 431 reference chip at the output, and then the control signal is transmitted to the FB pin through the optocoupler switch PC1.

[0053] The reference voltage of the control pin R of the 431 reference chip is 2.5V. If the input voltage of this pin is less than 2.5V, the pins K and A are in a high-impedance state, so the optocoupler switch PC1 is not turned on and the FB pin outputs a high voltage. If the voltage of this pin is higher than 2.5V, the pins K and A are in a low-impedance state, so the optocoupler switch is turned on and the voltage of the FB pin is pulled low.

[0054] If the adjusting switch KEYn is in the open state, n is a non-zero natural number of 1, 2, 3...n. The output voltage is divided by voltage divider resistors R36 and R40 and then connected to the control pin R of the 431 reference chip. After the 431 reference chip adjusts the FlyBuck control chip through optocoupler switch PC1, the control pin R of the 431 reference chip is always kept at 2.5V. Thus, the output voltage VOUT+=(R36+R40) / R40*2.5V.

[0055] If one of the switches KEYn, KEY1, is closed, the output voltage is divided by the voltage divider resistors R36 / / R40 and R40 and then connected to the control pin R of the 431 reference chip. Thus, the output voltage VOUT+ = (R36 / / R44+R40) / R40*2.5V.

[0056] Similarly, if several keys are closed, the corresponding resistors are connected in parallel with voltage divider resistor R36, and then divided by voltage divider resistor R40 before being connected to the control pin R of the 431 reference chip, thus obtaining different output voltages.

[0057] The maximum operating voltage of the 431 reference chip is approximately 30V. Output voltages exceeding 30V will damage the chip. Therefore, a voltage regulator circuit (R42 / DV1 / Q10) is added to power the chip. VOUT+ is stabilized at 18V by the DV1 regulator after passing through R42. This 18V voltage controls the base of transistor Q10, causing the emitter of Q10 to output a fixed voltage of 18V - 0.7V = 17.3V to power the 431 reference chip.

[0058] Because the power supply of the 431 reference chip is fixed at 17.3V, it is impossible to provide lead feedback through C24 / R38 during startup, which will cause output overshoot. Adding a lead feedback circuit with C25 and R43 can increase the amount of advance feedback.

[0059] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on the present invention to achieve substantially the same technical effect are all covered within the protection scope of the present invention.

Claims

1. A wide voltage output power supply circuit, comprising: a control chip; a field effect circuit, the control chip being electrically connected to the field effect circuit; at least one transformer; and at least one secondary side filter rectifier circuit, the field effect circuit being electrically connected to the secondary side filter rectifier circuit through the transformer, the secondary side filter rectifier circuit being electrically connected to a common mode inductor; characterized in that: it further comprises a voltage stabilizing circuit, a reference chip, a first leading feedback circuit, a second leading feedback circuit and at least one output voltage feedback circuit, the voltage stabilizing circuit and the reference chip being electrically connected to the control chip through a photo-coupler switch, the first leading feedback circuit being in parallel with the voltage stabilizing circuit and the reference chip, the second leading feedback circuit and the output voltage feedback circuit being in parallel and then being in series with the voltage stabilizing circuit, the reference chip and the first leading feedback circuit.

2. The wide range output power supply circuit according to claim 1, characterized by: the voltage stabilizing circuit comprises a transistor Q10, a resistor R42 and a voltage stabilizing diode DV1, the base of the transistor Q10 being connected to the resistor R42 and the voltage stabilizing diode DV1, the collector of the transistor Q10 being connected to the resistor R42, the second leading feedback circuit and the output voltage feedback circuit, the emitter of the transistor Q10 being connected to the photo-coupler switch, the reference chip and the first leading feedback circuit.

3. The wide range output power supply circuit of claim 1, wherein: the first leading feedback circuit comprises a capacitor C24 and a resistor R38 in series, the capacitor C24 being electrically connected to the photo-coupler switch, the reference chip and the voltage stabilizing circuit, the resistor R38 being electrically connected to the reference chip.

4. The wide range output power supply circuit of claim 3, wherein: it further comprises a resistor R34 and a resistor R35 in parallel, the voltage stabilizing circuit being electrically connected to the photo-coupler switch through the resistor R34, the voltage stabilizing circuit being electrically connected to the first leading feedback circuit, the reference chip and the photo-coupler switch through the resistor R35.

5. The wide range output power supply circuit of claim 3, wherein: it further comprises a voltage dividing resistor R36 and a voltage dividing resistor R40, the voltage dividing resistor R36 being in parallel with the second leading feedback circuit and the output voltage feedback circuit, the voltage dividing resistor R40 and the reference chip being in parallel and then being in series with the voltage dividing resistor R36, the second leading feedback circuit and the output voltage feedback circuit.

6. A wide range output power supply circuit according to claim 5, wherein: the voltage dividing resistor R40 and the reference chip being electrically connected to the voltage stabilizing circuit, the secondary side filter rectifier circuit and the common mode inductor.

7. The wide range output power supply circuit of claim 1, wherein: the second leading feedback circuit comprises a capacitor C25 and a resistor R43 in series, the capacitor C25 and the resistor R43 being in parallel with the output voltage feedback circuit.

8. The wide range output power supply circuit of claim 1, wherein: the output voltage feedback circuit comprises an adjusting switch and a resistor, the adjusting switch and the resistor being in series and then being in parallel with the second leading feedback circuit.

9. A wide range output power supply circuit according to any one of claims 1 to 8, characterized by: it further comprises a primary side AC filter rectifier circuit, a RCD spike absorption circuit and at least one RCD absorption circuit, the primary side AC filter rectifier circuit being electrically connected to the transformer through the RCD spike absorption circuit and the RCD absorption circuit.

10. A wide range output power supply circuit according to any one of claims 1 to 8, characterized by: it further comprises an auxiliary power supply circuit, the auxiliary power supply circuit being electrically connected to the transformer.

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