Ultra-wide voltage regulation stable output circuit

Abstract

The invention provides an ultra-wide voltage regulation stable output circuit which comprises a BUCK power supply module and a main power supply module. The main power supply module comprises a DCDC deformation control unit and a transformer output unit, the transformer output unit comprises at least two transformers, and the transformers are connected in a manner that primary sides are connected in parallel and multiple sides are connected in series, so that the output voltage of a transformer sub-circuit is adjusted according to a PWM2 signal. The ultra-wide voltage regulation stable output circuit has an ultra-wide voltage regulation range, stable output can be realized, a two-stage power supply topological structure is adopted, bus voltage reduction or direct connection can be realized by utilizing the first-stage BUCK power supply module, and the output voltage of the bus can be reduced by utilizing the second-stage BUCK power supply module. And the second-stage main power supply module is utilized to realize adjustable output in a larger range and stable output, so that the applicability and reliability of the circuit can be effectively improved, and the use requirements of different power supplies are met.

Description

Technical Field

[0001] The present invention belongs to the field of circuit technology, and in particular relates to an ultra-wide voltage regulation and stable output circuit. Background Art

[0002] With increasing industrial demand, some environments require power supplies with an extremely wide voltage regulation range. Traditional power supplies offer adjustable output voltages from 0 to 24V or 0 to 60V. These power supplies require output voltages that pose no safety risks to the human body. Power supplies exceeding safety voltages are rare on the market and generally require customization. For example, electrosurgical unit drivers typically offer an adjustable output voltage from 600V to 1000V. However, implementing such power supplies is challenging, requiring a two-stage power supply topology. The first stage requires a buck circuit capable of either stepping down or bypassing the bus voltage. To maintain steady-state operation at the second stage's low-voltage output, directly stepping down the bus voltage would result in unstable output due to the small duty cycle. Therefore, achieving a wider output range, such as 0 to 4kV, while ensuring stable output is a pressing issue. Summary of the Invention

[0003] In view of this, the present invention aims to provide an ultra-wide voltage regulation stable output circuit to solve the problem of unstable output of existing adjustable voltage output circuits.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows: An ultra-wide voltage regulation and stable output circuit includes a BUCK power supply module and a main power supply module; The BUCK power module includes a BUCK output unit and a PWM regulation unit. The PWM regulation unit is connected to the BUCK output unit to adjust the output voltage of the BUCK output unit according to the PWM1 signal. The main power supply module includes a DCDC deformation control unit and a transformer output unit. The DCDC deformation control unit includes a dual-switch flyback subcircuit, a voltage feedback and PWM regulation subcircuit, and a control subcircuit. The transformer output unit includes at least two transformers, each of which is connected in parallel with its primary side and in series with its secondary side. The input end of the dual-switch flyback subcircuit is connected to the output end of the BUCK output unit, and the output end of the dual-switch flyback subcircuit is connected to the primary side of each transformer. The voltage acquisition input end of the voltage feedback and PWM regulation subcircuit is connected to the secondary side of the transformer, and the feedback output end of the voltage feedback and PWM regulation subcircuit is connected to the control end of the dual-switch flyback subcircuit through the control subcircuit. The voltage feedback and PWM regulation subcircuit is provided with a signal input end for receiving a PWM2 regulation signal to adjust the output voltage of the transformer subcircuit according to the PWM2 signal.

[0005] Furthermore, the BUCK output unit includes a BUCK sub-circuit and a MOS transistor driving sub-circuit, and the low side of the BUCK sub-circuit is connected to the MOS transistor driving sub-circuit.

[0006] Furthermore, the PWM regulation unit includes a voltage negative feedback regulation subcircuit and an optocoupler isolation subcircuit. The voltage acquisition input end of the voltage negative feedback regulation subcircuit is connected to the high side of the BUCK subcircuit, the signal input end is used to receive the PWM regulation signal, and the feedback output end is connected to the input end of the optocoupler isolation subcircuit; the control end of the MOS tube drive subcircuit is connected to the output end of the optocoupler isolation subcircuit through a switching power supply to adjust the output voltage of the BUCK output unit according to the PWM1 signal.

[0007] Furthermore, the dual-tube flyback subcircuit includes a MOS tube Q5200, a MOS tube Q5201, a Zener diode ZD5200, a Zener diode ZD5201, a capacitor C5206, a capacitor C5213, a resistor R5221, a resistor R5222, a resistor R5240, a resistor R5242, a resistor R5251, a resistor R5252, a diode D5206, and a diode D5209; The gate and source of the MOS transistor Q5200 are both connected to the DRV output terminal of the control sub-circuit, the drain is connected to the high side of the BUCK sub-circuit, and the source of the MOS transistor Q5200 is the VP+ output of the dual-tube flyback sub-circuit; the cathode of the voltage stabilizing diode ZD5200 is connected to the gate of the MOS transistor Q5200, and the anode is connected to the source of the MOS transistor Q5200; one end of the resistor R5221 is connected to the gate of the MOS transistor Q5200, and the other end is connected to the source of the MOS transistor Q5200; the capacitor C5206 is connected in series with the resistor R5222, and one end is connected to the drain of the MOS transistor Q5200, and the other end is connected to the source of the MOS transistor Q5200; the cathode of the diode D5206 is connected to the drain of the MOS transistor Q5200, and the anode is connected to the drain of the MOS transistor Q5201; The gate of the MOS transistor Q5201 is connected to the DRV output terminal of the control sub-circuit, the source of the MOS transistor Q5201 is connected to the ISENSE input terminal of the control sub-circuit, and the drain of the MOS transistor Q5201 is the VP- output of the dual-tube flyback sub-circuit; the cathode of the voltage stabilizing diode ZD5201 is connected to the gate of the MOS transistor Q5201, and the anode is connected to the source of the MOS transistor Q5201; one end of the resistor R5242 is connected to the gate of the MOS transistor Q5201, and the other end is connected to the source of the MOS transistor Q5201; the resistors R5251 and R5252 are connected in parallel, one end of which is connected to the source of the MOS transistor Q5201, and the other end is grounded; the capacitor C5213 is connected in series with the resistor R5240, one end of which is connected to the drain of the MOS transistor Q5201, and the other end is connected to the source of the MOS transistor Q5201; the cathode of the diode D5209 is connected to the source of the MOS transistor Q5200, and the anode is grounded.

[0008] Furthermore, the voltage feedback and PWM regulation subcircuit includes an operational amplifier U5203A, an operational amplifier U5203B, a capacitor C5244, a capacitor C5245, a capacitor C5246, a capacitor C5247, a capacitor C5284, a resistor R5321, a resistor R5310, a resistor R5331, a resistor R5332, a resistor R5313, a resistor R5315, a resistor R5316, a resistor R5335, a resistor R5336, a resistor R5337, a resistor R5338, a resistor R5339, a resistor R5340, a resistor R5341 and a resistor R5342; The inverting input terminal of the operational amplifier U5203A is connected to its output terminal through a resistor R5321. The output terminal of the operational amplifier U5203A is the first voltage acquisition input terminal of the voltage feedback and PWM regulation subcircuit. The non-inverting input terminal of the operational amplifier U5203A is connected to the inverting input terminal of the operational amplifier U5203B through a resistor R5322. The output end of the operational amplifier U5203B is the feedback output end of the voltage feedback and PWM regulation subcircuit, and the inverting input end is grounded through the capacitor C5246; one end of the capacitor C4244 is connected to the inverting input end of the operational amplifier U5203B, and the other end is connected to the output end of the operational amplifier U5203B; the capacitor C5245 and the resistor R5310 are connected in series, and one end is connected to the inverting input end of the operational amplifier U5203B, and the other end is connected to the output end of the operational amplifier U5203B; one end of the resistor R5331 is connected to the non-inverting input end of the operational amplifier U5203B, and the other end is the signal input end of the voltage feedback and PWM regulation subcircuit; the resistor R5332 and the capacitor C5247 are connected in parallel, and one end is connected to the non-inverting output end of the operational amplifier U5203B, and the other end is grounded; One end of the resistor R5337 is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded through the resistors R5336, R5335, R5338, R5339, R5340, R5341 and R5342 connected in series in sequence. The connection between the resistors R5335 and R5338 is the second voltage collection input terminal of the voltage feedback and PWM regulation subcircuit, and the connection between the resistors R5340 and R5341 is the overvoltage protection voltage collection input terminal of the voltage feedback and PWM regulation subcircuit. One end of the capacitor C5284 is connected to the overvoltage protection voltage collection input terminal, and the other end is grounded; the resistor R5313 and the resistor R5316 are connected in series, and one end is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded; one end of the resistor R5315 is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded.

[0009] Furthermore, the DCDC deformation control unit further includes a photoelectric isolation subcircuit, and the feedback output end of the voltage feedback and PWM regulation subcircuit is connected to the control subcircuit through the photoelectric isolation subcircuit.

[0010] Furthermore, the photoelectric isolation sub-circuit includes an optical coupler U5205, a resistor R5312, and a resistor R5314; The anode of the optocoupler U5205 is connected to the power supply 12VCC1 through the resistor R5312, and the cathode is connected to the output end of the operational amplifier U5203B; one end of the resistor R5314 is connected to the anode of the optocoupler U5205, and the other end is connected to the cathode of the optocoupler U5205; the collector of the optocoupler U5205 is connected to the control subcircuit, and the emitter is grounded.

[0011] Compared with the prior art, the ultra-wide voltage regulation and stable output circuit described in the present invention has the following advantages: (1) The ultra-wide voltage regulation and stable output circuit described in the present invention has an ultra-wide voltage regulation range and can achieve stable output. By adopting a two-stage power supply topology, the first-stage BUCK power supply module can be used to achieve bus voltage reduction or direct pass-through, and the second-stage main power supply module can be used to achieve a wider range of output adjustment and stable output. This can effectively improve the applicability and reliability of this circuit, meet different power supply usage needs, and has a broad market application prospect.

[0012] (2) The ultra-wide voltage regulation and stable output circuit described in the present invention can achieve stable output of low and high voltages. When outputting low voltage, the first-stage BUCK power module is first adjusted to a voltage higher than the output voltage, and then further adjusted by the second-stage main power module to achieve low voltage output. This is relatively easy to implement and can ensure the output stability of the circuit. When it is necessary to ensure stable high-voltage output, the BUCK power module and the main power module can cooperate to achieve direct bus voltage conversion, reducing system losses and improving the stability of the circuit output. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1 This is a schematic diagram of the circuit structure of a BUCK output unit in an ultra-wide voltage regulation and stable output circuit according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the circuit structure of a PWM regulation unit in an ultra-wide voltage regulation and stable output circuit according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the circuit structure of a dual-switch flyback circuit in an ultra-wide voltage regulation and stable output circuit according to an embodiment of the present invention; Figure 4 A schematic diagram of the circuit structure of a voltage feedback and PWM regulation subcircuit in an ultra-wide voltage regulation and stable output circuit according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the circuit structure of a control subcircuit in an ultra-wide voltage regulation and stable output circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0015] An ultra-wide voltage regulation stable output circuit, such as Figures 1 to 5 As shown, it includes a buck power module and a main power module.

[0016] The BUCK power supply module includes a BUCK output unit and a PWM regulation unit. The PWM regulation unit is connected to the BUCK output unit to adjust the output voltage of the BUCK output unit according to a PWM1 signal.

[0017] The main power supply module includes a DC-DC transformation control unit and a transformer output unit. The DC-DC transformation control unit includes a dual-switch flyback subcircuit, a voltage feedback and PWM regulation subcircuit, and a control subcircuit. The transformer output unit includes at least two transformers, each of which is connected in parallel on its primary side and in series on its secondary side. The input of the dual-switch flyback subcircuit is connected to the output of the BUCK output unit, and the output of the dual-switch flyback subcircuit is connected to the primary side of each transformer. The voltage acquisition input of the voltage feedback and PWM regulation subcircuit is connected to the secondary side of the transformer, and the feedback output of the voltage feedback and PWM regulation subcircuit is connected to the control end of the dual-switch flyback subcircuit via the control subcircuit. The voltage feedback and PWM regulation subcircuit is provided with a signal input for receiving a PWM2 regulation signal to adjust the output voltage of the transformer subcircuit according to the PWM2 signal.

[0018] Preferably, the BUCK output unit includes a BUCK sub-circuit and a MOS transistor driver sub-circuit, wherein the low side of the BUCK sub-circuit is connected to the MOS transistor driver sub-circuit. Exemplarily, the low side of the BUCK sub-circuit is its low voltage end, and the high side of the BUCK sub-circuit is its high voltage end.

[0019] In actual applications, the buck sub-circuit can use an existing buck circuit. However, the buck circuit's driving method needs to be considered. Placing the MOS transistor on the high side or low side of the buck circuit will result in different circuit structures. Conventional buck circuits with low-voltage inputs and outputs are relatively simple to drive, regardless of whether the MOS transistor is placed on the high side or low side. However, if the input voltage exceeds 100V, driving an NMOS transistor becomes more complicated. Furthermore, PMOS transistors with better parameters are relatively expensive, increasing circuit costs.

[0020] Therefore, by placing the MOS transistor at the low-side output of the buck circuit—that is, connecting the low-side of the buck subcircuit to the MOS transistor driver subcircuit—low-side drive can be achieved, with lower requirements for the MOS transistor. Furthermore, by providing an isolated feedback module, both isolation and synchronization with a given reference are achieved, giving this output-adjustable circuit a certain degree of anti-interference capability.

[0021] Preferably, the PWM regulation unit includes a voltage negative feedback regulation subcircuit and an optocoupler isolation subcircuit, the voltage acquisition input end of the voltage negative feedback regulation subcircuit is connected to the high side of the BUCK subcircuit, the signal input end is used to receive the PWM regulation signal, and the feedback output end is connected to the input end of the optocoupler isolation subcircuit; the control end of the MOS tube drive subcircuit is connected to the output end of the optocoupler isolation subcircuit through a switching power supply to adjust the output voltage of the BUCK output unit according to the PWM1 signal.

[0022] For example, the switching power supply can be an existing UC3842 switching power supply. Those skilled in the art may also select other switching power supplies based on actual needs, which will not be described in detail here. In actual use, by adjusting the PWM1 signal, closed-loop feedback of the output voltage of the buck output unit can be achieved, thereby adjusting the output voltage.

[0023] Optionally, the voltage negative feedback regulation subcircuit includes an operational amplifier U5102A, a resistor R5120, a capacitor C5109, and a capacitor C5103. Specifically, the non-inverting input of the operational amplifier U5102A is connected to the output of the operational amplifier U5102B via a resistor R5116, and the inverting input is connected to the high side of the BUCK subcircuit; after the resistor R5120 and the capacitor C5109 are connected in series, one end is connected to the inverting input of the operational amplifier U5102A, and the other end is connected to the output of the operational amplifier U5102A; the capacitor C5103 has one end connected to the inverting input of the operational amplifier U5102A, and the other end is connected to the output of the operational amplifier U5102A.

[0024] In actual application, the voltage negative feedback regulation subcircuit also includes a resistor R5137, a capacitor C5118, a Zener diode ZD5102, a resistor R5111, a resistor R5143, a resistor R5121, a resistor R5123, a resistor R5134, and a capacitor C5124.

[0025] Specifically, the positive power supply terminal of the operational amplifier U5102A is connected to the power supply 12VCC1 through the resistor R5137, and the negative power supply terminal is grounded; one end of the capacitor C5118 is connected to the positive power supply terminal of the operational amplifier U5102A, and the other end is grounded; the positive pole of the voltage regulator diode ZD5102 is grounded, and the negative pole is connected to the power supply 12VCC1 through the resistor R5137; the inverting input terminal of the operational amplifier U5102A is connected to the high side of the BUCK sub-circuit through the resistor R5121, the resistor R5143, and the resistor R5111 connected in series in sequence; after the resistor R5123 is connected in series with the resistor R5134, one end is connected to the inverting input terminal of the operational amplifier U5102A, and the other end is grounded; one end of the capacitor C5124 is connected to the inverting input terminal of the operational amplifier U5102A, and the other end is grounded.

[0026] Optionally, the optocoupler isolator circuit includes a resistor R5107, a resistor R5108, an optocoupler U5101, and a capacitor C5108. The optocoupler U5101 can be an existing device, and the power supply and connection method of the optocoupler are common knowledge to those skilled in the art and will not be described in detail here.

[0027] Specifically, the anode of the optocoupler U5101 is connected to the power supply 12VCC1 through the resistor R5108, and the cathode is connected to the output end of the operational amplifier U5102A; one end of the resistor R5107 is connected to the anode of the optocoupler U5101, and the other end is connected to the cathode of the optocoupler U5101; the collector of the optocoupler U5101 is connected to the control end of the MOS tube drive subcircuit through the switching power supply, and the emitter is grounded; one end of the capacitor C5108 is connected to the collector of the optocoupler U5101, and the other end is connected to the emitter of the optocoupler U5101.

[0028] Optionally, the MOS transistor driving subcircuit includes a MOS transistor Q5100, a capacitor C5100, a resistor R5101, a resistor R5115, a resistor R5104, and a Zener diode ZD5100. For example, the MOS transistor Q5100 may be a MOS transistor of model ipa60r060p7xksa1.

[0029] Specifically, the gate of the MOS transistor Q5100 is connected to the collector of the optocoupler U5101 via a switching power supply, the drain is connected to the low side of the BUCK sub-circuit, and the source is grounded via a resistor R5115. The capacitor C5100 is connected in series with the resistor R5101, with one end connected to the drain of the MOS transistor Q5100 and the other end connected to the source of the MOS transistor Q5100. The resistor R5104 has one end connected to the gate of the MOS transistor Q5100 and the other end connected to ground. The positive electrode of the zener diode ZD5100 is grounded, and the negative electrode is connected to the gate of the MOS transistor Q5100. Those skilled in the art may also select other suitable MOS transistor driving sub-circuits according to actual needs to achieve driving of the BUCK sub-circuit, and this will not be described in detail here.

[0030] Preferably, the dual-tube flyback subcircuit includes MOS tube Q5200, MOS tube Q5201, Zener diode ZD5200, Zener diode ZD5201, capacitor C5206, capacitor C5213, resistor R5221, resistor R5222, resistor R5240, resistor R5242, resistor R5251, resistor R5252, diode D5206 and diode D5209.

[0031] Specifically, the gate and source of the MOS transistor Q5200 are both connected to the DRV output terminal of the control sub-circuit, the drain is connected to the high side of the BUCK sub-circuit, and the source of the MOS transistor Q5200 is the VP+ output of the dual-tube flyback sub-circuit; the cathode of the voltage stabilizing diode ZD5200 is connected to the gate of the MOS transistor Q5200, and the anode is connected to the source of the MOS transistor Q5200; one end of the resistor R5221 is connected to the gate of the MOS transistor Q5200, and the other end is connected to the source of the MOS transistor Q5200; the capacitor C5206 is connected in series with the resistor R5222, and one end is connected to the drain of the MOS transistor Q5200, and the other end is connected to the source of the MOS transistor Q5200; the cathode of the diode D5206 is connected to the drain of the MOS transistor Q5200, and the anode is connected to the drain of the MOS transistor Q5201.

[0032] The gate of the MOS transistor Q5201 is connected to the DRV output terminal of the control sub-circuit, the source of the MOS transistor Q5201 is connected to the ISENSE input terminal of the control sub-circuit, and the drain of the MOS transistor Q5201 is the VP- output of the dual-transistor flyback sub-circuit; the cathode of the voltage stabilizing diode ZD5201 is connected to the gate of the MOS transistor Q5201, and the anode is connected to the source of the MOS transistor Q5201; one end of the resistor R5242 is connected to the gate of the MOS transistor Q5201, and the other end is connected to the source of the MOS transistor Q5201; the resistors R5251 and R5252 are connected in parallel, one end is connected to the source of the MOS transistor Q5201, and the other end is grounded; the capacitor C5213 is connected in series with the resistor R5240, one end is connected to the drain of the MOS transistor Q5201, and the other end is connected to the source of the MOS transistor Q5201; the cathode of the diode D5209 is connected to the source of the MOS transistor Q5200, and the anode is grounded.

[0033] In actual applications, the main power supply module, serving as the main power topology for high-voltage output, adopts a modified dual-transistor flyback circuit topology, known as a DC-DC modified control unit. This topology optimizes the selection of primary-side MOS transistors and effectively clamps primary-side spike voltages. Furthermore, the DC-DC modified topology is suitable for higher-power output environments. Furthermore, the transformer output unit utilizes two transformer primary sides connected in parallel and their secondary sides in series. However, those skilled in the art can also configure three, four, or more transformers, each with its primary side connected in parallel and its secondary sides in series, as needed.

[0034] It should be noted that two transformers are generally sufficient to meet the topological design requirements for high-voltage output. Due to safety regulations and high-voltage requirements, using a conventional single transformer presents significant difficulties in designing the number of turns. The complex winding requires a large number of turns. Too many turns will cause large leakage inductance, resulting in voltage spikes and affecting the stability of low-voltage output. It is also difficult to select high-voltage output rectifier components. Therefore, the transformer primary windings are connected in parallel, and the complex windings are connected in series. The high-voltage output is divided into 14 windings, each of which is equivalent to completing a voltage of 200V to 300V. The final series connection ensures that the number of turns of each winding is not too large, reduces leakage inductance, and simplifies the selection of rectifier components.

[0035] Alternatively, the control subcircuit utilizes an existing current-mode PWM controller, such as the UC2845 or UC2845, as the control chip U5202. Those skilled in the art can also adjust the PWM signal through existing feedback and compensation mechanisms. As the output voltage increases, the feedback voltage rises, reducing the error amplifier output, which in turn reduces the PWM duty cycle and, consequently, the output voltage; and vice versa. To achieve optimal system dynamic performance and stability, the compensation network can be designed based on actual needs, including selecting appropriate resistor and capacitor values ​​to adjust the frequency response. These choices are within the skill of those skilled in the art and will not be elaborated upon here.

[0036] Preferably, the voltage feedback and PWM regulation subcircuit includes an operational amplifier U5203A, an operational amplifier U5203B, a capacitor C5244, a capacitor C5245, a capacitor C5246, a capacitor C5247, a capacitor C5284, a resistor R5321, a resistor R5310, a resistor R5331, a resistor R5332, a resistor R5313, a resistor R5315, a resistor R5316, a resistor R5335, a resistor R5336, a resistor R5337, a resistor R5338, a resistor R5339, a resistor R5340, a resistor R5341 and a resistor R5342.

[0037] Specifically, the inverting input terminal of the operational amplifier U5203A is connected to its output terminal through the resistor R5321. The output terminal of the operational amplifier U5203A is the first voltage acquisition input terminal of the voltage feedback and PWM regulation subcircuit. The non-inverting input terminal of the operational amplifier U5203A is connected to the inverting input terminal of the operational amplifier U5203B through the resistor R5322.

[0038] Among them, the output end of the operational amplifier U5203B is the feedback output end of the voltage feedback and PWM regulation sub-circuit, and the inverting input end is grounded through the capacitor C5246; one end of the capacitor C4244 is connected to the inverting input end of the operational amplifier U5203B, and the other end is connected to the output end of the operational amplifier U5203B; the capacitor C5245 and the resistor R5310 are connected in series, and one end is connected to the inverting input end of the operational amplifier U5203B, and the other end is connected to the output end of the operational amplifier U5203B; one end of the resistor R5331 is connected to the non-inverting input end of the operational amplifier U5203B, and the other end is the signal input end of the voltage feedback and PWM regulation sub-circuit; the resistor R5332 and the capacitor C5247 are connected in parallel, and one end is connected to the non-inverting output end of the operational amplifier U5203B, and the other end is grounded.

[0039] Secondly, one end of resistor R5337 is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded through resistors R5336, R5335, R5338, R5339, R5340, R5341 and R5342 connected in series in sequence. The connection point between resistors R5335 and R5338 is the second voltage collection input terminal of the voltage feedback and PWM regulation subcircuit, and the connection point between resistors R5340 and R5341 is the overvoltage protection voltage collection input terminal of the voltage feedback and PWM regulation subcircuit. One end of capacitor C5284 is connected to the overvoltage protection voltage collection input terminal, and the other end is grounded; the resistor R5313 and resistor R5316 are connected in series, and one end is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded; one end of the resistor R5315 is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded.

[0040] It should be noted that in addition to designing the first voltage acquisition input terminal, the second voltage acquisition input terminal and the overvoltage protection voltage acquisition input terminal in the voltage feedback and PWM regulation subcircuit, technical personnel in this field can also set other voltage acquisition input terminals according to actual needs to realize the acquisition of the transformer complex side voltage, which is conducive to improving the stability of the circuit output.

[0041] In actual applications, the PWM1 and PWM2 signals are different PWM signals used to control the two power supplies, respectively. Synchronous adjustment of the output voltage can be achieved by simultaneously adjusting the PWM1 signal of the buck power module and the PWM2 signal of the main power module. The PWM1 and PWM2 signals can be provided by different controllers. Alternatively, the PWM1 and PWM2 adjustment signals can be provided by other existing controllers, such as a single-chip microcomputer. Persons skilled in the art can also select an appropriate signal source based on actual needs, and this will not be elaborated here.

[0042] Specifically, when the output voltage is high, the PWM1 signal can be executed at full duty cycle, which is equivalent to the buck circuit in the buck power module being directly switched on, thereby reducing losses. At this time, when the system needs to ensure high-voltage output, the buck pole is directly switched on, which is equivalent to directly converting the bus voltage to the input pole of the dual-switch flyback circuit, reducing system losses while ensuring system stability. When the system requires a lower output voltage of approximately 10V or 20V, the buck output unit's duty cycle must first be adjusted to an output of approximately 40V. This makes the buck output unit the input pole of the DC-DC converter control unit. A 40V input can easily be self-generated to a 10 to 20V output through the dual-switch flyback circuit. At the same time, a relatively large duty cycle can be used to ensure system stability.

[0043] Preferably, the DCDC deformation control unit further includes a photoelectric isolation subcircuit, through which the feedback output of the voltage feedback and PWM regulation subcircuit is connected to the control subcircuit. Providing the photoelectric isolation subcircuit helps reduce the impact of interference on signal transmission and improves signal transmission reliability.

[0044] Specifically, the optocoupler U5205, a resistor R5312, and a resistor R5314 are included in the optocoupler. The anode of the optocoupler U5205 is connected to the power supply 12VCC1 via the resistor R5312, and the cathode is connected to the output of the operational amplifier U5203B. One end of the resistor R5314 is connected to the anode of the optocoupler U5205, and the other end is connected to the cathode of the optocoupler U5205. The collector of the optocoupler U5205 is connected to the control subcircuit, and the emitter is grounded.

[0045] The ultra-wide voltage regulation and stable output circuit described in the present invention has an ultra-wide voltage regulation range and can achieve stable output. By adopting a two-stage power supply topology, the first-stage BUCK power supply module can be used to achieve bus voltage reduction or direct pass-through, and the second-stage main power supply module can be used to achieve a wider range of output adjustment and stable output. This can effectively improve the applicability and reliability of this circuit, meet different power supply usage needs, and have a broad market application prospect. This circuit can achieve stable output of low and high voltages. When outputting low voltage, the first-stage BUCK power supply module is first adjusted to a voltage higher than the output voltage, and then further adjusted by the second-stage main power supply module to achieve low voltage output. This is relatively easy to implement and can ensure the stability of the circuit output. When it is necessary to ensure the stability of high-voltage output, the BUCK power supply module and the main power supply module can cooperate to achieve direct bus voltage conversion, reducing system losses while also improving the stability of the circuit output.

[0046] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. An ultra-wide voltage regulation and stable output circuit, characterized in that: Including BUCK power module and main power module; The BUCK power module includes a BUCK output unit and a PWM regulation unit. The PWM regulation unit is connected to the BUCK output unit to adjust the output voltage of the BUCK output unit according to the PWM1 signal. The main power supply module includes a DCDC deformation control unit and a transformer output unit. The DCDC deformation control unit includes a dual-switch flyback subcircuit, a voltage feedback and PWM regulation subcircuit, and a control subcircuit. The transformer output unit includes at least two transformers, each of which is connected in parallel with its primary side and in series with its secondary side. The input end of the dual-switch flyback subcircuit is connected to the output end of the BUCK output unit, and the output end of the dual-switch flyback subcircuit is connected to the primary side of each transformer. The voltage acquisition input end of the voltage feedback and PWM regulation subcircuit is connected to the secondary side of the transformer, and the feedback output end of the voltage feedback and PWM regulation subcircuit is connected to the control end of the dual-switch flyback subcircuit through the control subcircuit. The voltage feedback and PWM regulation subcircuit is provided with a signal input end for receiving a PWM2 regulation signal to adjust the output voltage of the transformer subcircuit according to the PWM2 signal.

2. The ultra-wide voltage regulation and stable output circuit according to claim 1, characterized in that: The BUCK output unit includes a BUCK sub-circuit and a MOS transistor driving sub-circuit, and the low side of the BUCK sub-circuit is connected to the MOS transistor driving sub-circuit.

3. The ultra-wide voltage regulation and stable output circuit according to claim 2, characterized in that: The PWM regulation unit includes a voltage negative feedback regulation subcircuit and an optocoupler isolation subcircuit. The voltage acquisition input terminal of the voltage negative feedback regulation subcircuit is connected to the high side of the BUCK subcircuit, the signal input terminal is used to receive the PWM regulation signal, and the feedback output terminal is connected to the input terminal of the optocoupler isolation subcircuit. The control terminal of the MOS transistor drive subcircuit is connected to the output terminal of the optocoupler isolation subcircuit through a switching power supply to adjust the output voltage of the BUCK output unit according to the PWM1 signal.

4. The ultra-wide voltage regulation and stable output circuit according to claim 1, characterized in that: The gate and source of the MOS transistor Q5200 are both connected to the DRV output terminal of the control sub-circuit, the drain is connected to the high side of the BUCK sub-circuit, and the source of the MOS transistor Q5200 is the VP+ output of the dual-tube flyback sub-circuit; the cathode of the zener diode ZD5200 is connected to the gate of the MOS transistor Q5200, and the anode is connected to the source of the MOS transistor Q5200; One end of the resistor R5221 is connected to the gate of the MOS transistor Q5200, and the other end is connected to the source of the MOS transistor Q5200; the capacitor C5206 is connected in series with the resistor R5222, and one end is connected to the drain of the MOS transistor Q5200, and the other end is connected to the source of the MOS transistor Q5200; the cathode of the diode D5206 is connected to the drain of the MOS transistor Q5200, and the anode is connected to the drain of the MOS transistor Q5201; The gate of the MOS transistor Q5201 is connected to the DRV output terminal of the control sub-circuit, the source of the MOS transistor Q5201 is connected to the ISENSE input terminal of the control sub-circuit, and the drain of the MOS transistor Q5201 is the VP- output of the dual-tube flyback sub-circuit; the cathode of the voltage stabilizing diode ZD5201 is connected to the gate of the MOS transistor Q5201, and the anode is connected to the source of the MOS transistor Q5201; one end of the resistor R5242 is connected to the gate of the MOS transistor Q5201, and the other end is connected to the source of the MOS transistor Q5201; The resistors R5251 and R5252 are connected in parallel, with one end connected to the source of the MOS transistor Q5201 and the other end connected to ground. The capacitor C5213 and the resistor R5240 are connected in series, with one end connected to the drain of the MOS transistor Q5201 and the other end connected to the source of the MOS transistor Q5201. The cathode of the diode D5209 is connected to the source of the MOS transistor Q5200, and the anode is grounded.

5. The ultra-wide voltage regulation and stable output circuit according to claim 1, characterized in that: The voltage feedback and PWM regulation subcircuit includes an operational amplifier U5203A, an operational amplifier U5203B, a capacitor C5244, a capacitor C5245, a capacitor C5246, a capacitor C5247, a capacitor C5284, a resistor R5321, a resistor R5310, a resistor R5331, a resistor R5332, a resistor R5313, a resistor R5315, a resistor R5316, a resistor R5335, a resistor R5336, a resistor R5337, a resistor R5338, a resistor R5339, a resistor R5340, a resistor R5341 and a resistor R5342; The inverting input terminal of the operational amplifier U5203A is connected to its output terminal through a resistor R5321. The output terminal of the operational amplifier U5203A is the first voltage acquisition input terminal of the voltage feedback and PWM regulation subcircuit. The non-inverting input terminal of the operational amplifier U5203A is connected to the inverting input terminal of the operational amplifier U5203B through a resistor R5322. The output end of the operational amplifier U5203B is the feedback output end of the voltage feedback and PWM regulation subcircuit, and the inverting input end is grounded through the capacitor C5246; one end of the capacitor C4244 is connected to the inverting input end of the operational amplifier U5203B, and the other end is connected to the output end of the operational amplifier U5203B; the capacitor C5245 and the resistor R5310 are connected in series, and one end is connected to the inverting input end of the operational amplifier U5203B, and the other end is connected to the output end of the operational amplifier U5203B; one end of the resistor R5331 is connected to the non-inverting input end of the operational amplifier U5203B, and the other end is the signal input end of the voltage feedback and PWM regulation subcircuit; the resistor R5332 and the capacitor C5247 are connected in parallel, and one end is connected to the non-inverting output end of the operational amplifier U5203B, and the other end is grounded; One end of the resistor R5337 is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded through the resistors R5336, R5335, R5338, R5339, R5340, R5341 and R5342 connected in series in sequence. The connection between the resistors R5335 and R5338 is the second voltage collection input terminal of the voltage feedback and PWM regulation subcircuit, and the connection between the resistors R5340 and R5341 is the overvoltage protection voltage collection input terminal of the voltage feedback and PWM regulation subcircuit. One end of the capacitor C5284 is connected to the overvoltage protection voltage collection input terminal, and the other end is grounded; the resistor R5313 and the resistor R5316 are connected in series, and one end is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded; one end of the resistor R5315 is connected to the inverting input terminal of the operational amplifier U5203B, and the other end is grounded.

6. The ultra-wide voltage regulation and stable output circuit according to claim 5, characterized in that: The DCDC deformation control unit further includes a photoelectric isolation subcircuit, and the feedback output end of the voltage feedback and PWM regulation subcircuit is connected to the control subcircuit through the photoelectric isolation subcircuit.

7. The ultra-wide voltage regulation and stable output circuit according to claim 6, characterized in that: The optoelectronic isolation subcircuit includes an optocoupler U5205, a resistor R5312, and a resistor R5314; the anode of the optocoupler U5205 is connected to the power supply 12VCC1 through the resistor R5312, and the cathode is connected to the output end of the operational amplifier U5203B; one end of the resistor R5314 is connected to the anode of the optocoupler U5205, and the other end is connected to the cathode of the optocoupler U5205; the collector of the optocoupler U5205 is connected to the control subcircuit, and the emitter is grounded.

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