Power supply circuit

Abstract

The utility model provides a power supply circuit, comprising an input voltage regulating circuit which adopts a switching power supply structure and is used for regulating an input voltage to a first target voltage; the control execution circuit is used for adjusting the first target voltage to the second target voltage; the output filter circuit is used for filtering the second target voltage; the output end of the feedback signal processing circuit is electrically connected with the control end of the control execution circuit, and the first input end of the feedback signal processing circuit is electrically connected with the output end of the feedback signal processing circuit and the output end of the output filter circuit; the feedback signal processing circuit is used for feeding back a second target voltage and a reference voltage comparison signal and feeding back a voltage at the output end of the feedback signal processing circuit and the reference voltage comparison signal; and the reference voltage circuit is used for outputting reference voltage to the second input end of the feedback signal processing circuit. According to the utility model, the low-ripple large-current power supply circuit is constructed with low cost.

Description

Technical Field

[0001] This utility model relates to the field of electronic circuit technology, and in particular to a power supply circuit. Background Technology

[0002] For power supply circuits that convert direct current (DC) to different DC voltages for output, the commonly used solutions in the prior art are switching power supplies or linear power supplies. Switching power supplies typically have high current output capabilities, but their ripple suppression capabilities are poor. Linear power supplies typically have good ripple suppression capabilities, but they cannot output high current. Therefore, in the prior art, it is usually difficult to simultaneously meet the requirements of low ripple and high current output. Utility Model Content

[0003] The power supply circuit provided by this invention can be used to construct a low-ripple, high-current power supply circuit at a lower cost.

[0004] This utility model provides a power supply circuit, including:

[0005] An input voltage regulation circuit, which adopts a switching power supply structure, is used to adjust the input voltage to a first target voltage.

[0006] A control execution circuit, wherein the input terminal of the control execution circuit is electrically connected to the output terminal of the input voltage regulation circuit, and the control execution circuit is used to adjust the first target voltage to the second target voltage;

[0007] An output filtering circuit, wherein the input terminal of the output filtering circuit is electrically connected to the output terminal of the control execution circuit, and the output filtering circuit is used to filter the second target voltage;

[0008] A feedback signal processing circuit is provided, wherein the output terminal of the feedback signal processing circuit is electrically connected to the control terminal of the control execution circuit, and the first input terminal of the feedback signal processing circuit is electrically connected to the output terminal of the feedback signal processing circuit and the output terminal of the output filter circuit. The feedback signal processing circuit is used to feed back the comparison signal between the second target voltage and the reference voltage, and to feed back the comparison signal between the output voltage and the reference voltage of the feedback signal processing circuit.

[0009] A reference voltage circuit is provided, which adopts a linear power supply structure. The output terminal of the reference voltage circuit is electrically connected to the second input terminal of the feedback signal processing circuit. The reference voltage circuit is used to output the reference voltage.

[0010] Optionally, the input voltage regulation circuit includes:

[0011] A synchronous buck converter chip, wherein the input terminal of the synchronous buck converter chip is electrically connected to an input voltage source;

[0012] The first inductor, the first end of the first inductor being electrically connected to the switching pin of the synchronous buck converter chip;

[0013] The first resistor, the first end of which is electrically connected to the feedback pin of the synchronous buck converter chip;

[0014] The second resistor has its first end electrically connected to the second end of the first resistor, and its second end is electrically connected to the second end of the first inductor.

[0015] The third resistor has its first end electrically connected to the first end of the first resistor, and its second end electrically connected to the resistor ground pin of the synchronous buck converter chip.

[0016] A first capacitor, with its first terminal electrically connected to the second terminal of the second resistor, and its second terminal grounded; the first terminal of the first capacitor is used to output a first target voltage.

[0017] The second capacitor has its first terminal electrically connected to the first terminal of the first capacitor, and its second terminal grounded.

[0018] The third capacitor has its first terminal electrically connected to the first terminal of the second capacitor, and its second terminal grounded.

[0019] The fourth resistor has its first end electrically connected to the second end of the third resistor, and its second end is grounded.

[0020] A bootstrap capacitor, the first terminal of which is electrically connected to the switching pin of the synchronous buck converter chip;

[0021] A bootstrap resistor, wherein the first end of the bootstrap resistor is electrically connected to the bootstrap pin of the synchronous buck converter chip, and the second end of the bootstrap resistor is electrically connected to the second end of the bootstrap capacitor;

[0022] A grounding resistor, wherein the first end of the grounding resistor is electrically connected to the first end of the first inductor;

[0023] A grounding capacitor, wherein the first end of the grounding capacitor is electrically connected to the second end of the grounding resistor, and the second end of the grounding capacitor is grounded.

[0024] Optionally, the input voltage regulation circuit further includes an input filtering module, the input filtering module comprising:

[0025] A filter bead, wherein the first end of the filter bead is electrically connected to the input voltage source;

[0026] A first filter capacitor, wherein a first terminal of the first filter capacitor is electrically connected to a second terminal of the filter bead, and the second terminal of the first filter capacitor is grounded;

[0027] The second filter capacitor has its first terminal electrically connected to the first terminal of the first filter capacitor, and its second terminal grounded.

[0028] The third filter capacitor has its first terminal electrically connected to the first terminal of the second filter capacitor, and its second terminal grounded.

[0029] The fourth filter capacitor has its first terminal electrically connected to the first terminal of the third filter capacitor, and its first terminal electrically connected to the input terminal of the synchronous buck converter chip. The second terminal of the third filter capacitor is grounded.

[0030] Optionally, the input voltage regulation circuit further includes a first peripheral module, the first peripheral module comprising:

[0031] The first peripheral resistor has its first end electrically connected to the internal voltage pin of the synchronous buck converter chip, and its second end electrically connected to the drive decoupling input pin of the synchronous buck converter chip.

[0032] A first peripheral capacitor, wherein a first terminal of the first peripheral capacitor is electrically connected to a first terminal of the first peripheral resistor, and a second terminal of the first peripheral capacitor is grounded;

[0033] The second peripheral capacitor has its first terminal electrically connected to the second terminal of the first peripheral resistor, and its second terminal is grounded.

[0034] The third peripheral capacitor has its first terminal electrically connected to the soft-start input pin of the synchronous buck converter chip, and its second terminal grounded.

[0035] The second peripheral resistor has its first end electrically connected to the valley current setting pin of the synchronous buck converter chip, and its second end grounded.

[0036] The third peripheral resistor has its first end electrically connected to the operation mode selection pin of the synchronous buck converter chip, and its second end electrically connected to the first end of the first peripheral resistor.

[0037] The fourth peripheral resistor has its first end electrically connected to the protection mode selection pin of the synchronous buck converter chip, and its second end electrically connected to the second end of the third peripheral resistor.

[0038] Optionally, the input voltage regulation circuit further includes a second peripheral module, the second peripheral module including:

[0039] The fifth peripheral resistor, the first end of which is electrically connected to the operating signal transmission pin of the synchronous buck converter chip;

[0040] The sixth peripheral resistor has its first end electrically connected to the operating signal receiving pin of the synchronous buck converter chip, and its second end electrically connected to the second end of the fifth peripheral resistor.

[0041] The seventh peripheral resistor has its first end electrically connected to the current sensing output pin of the synchronous buck converter chip, and its second end electrically connected to the feedback pin of the synchronous buck converter chip.

[0042] The eighth peripheral resistor has its first end electrically connected to the internal slope compensation selection pin of the synchronous buck converter chip, and its second end grounded.

[0043] The ninth peripheral resistor has its first end electrically connected to the switching frequency pin of the synchronous buck converter chip, and its second end grounded.

[0044] Optionally, the control execution circuit includes:

[0045] The first MOSFET has its first terminal electrically connected to the first terminal of the first capacitor, and its second terminal is used to output the second target voltage.

[0046] The fourth capacitor has its first terminal electrically connected to the first terminal of the first MOS transistor, and its second terminal grounded.

[0047] The fifth capacitor has its first terminal electrically connected to the first terminal of the fourth capacitor, and its second terminal grounded.

[0048] The fifth resistor has its first end electrically connected to the third end of the first MOS transistor, and its second end grounded.

[0049] The sixth resistor has its first end electrically connected to the first end of the fifth resistor, and its second end serves as the control terminal of the control execution circuit. The second end of the sixth resistor is also electrically connected to the output terminal of the feedback signal processing circuit.

[0050] Optionally, the output filtering circuit includes:

[0051] The sixth capacitor has its first terminal electrically connected to the second terminal of the first MOS transistor, and its second terminal grounded.

[0052] The seventh capacitor has its first terminal electrically connected to the first terminal of the sixth capacitor, and its second terminal grounded.

[0053] The eighth capacitor has its first terminal electrically connected to the first terminal of the seventh capacitor, and its second terminal grounded. The first terminal of the eighth capacitor is used to output the filtered second target voltage.

[0054] Optionally, the feedback signal processing circuit includes:

[0055] A comparator, the output of which is electrically connected to the second terminal of the sixth resistor; the first input of the comparator serves as the first input of the feedback signal processing circuit, and the second input of the comparator serves as the second input of the feedback signal processing circuit.

[0056] A seventh resistor, the first end of which is electrically connected to the output terminal of the comparator, and the second end of which is electrically connected to the first input terminal of the comparator;

[0057] A ninth capacitor, wherein the first terminal of the ninth capacitor is electrically connected to the first terminal of the seventh resistor, and the second terminal of the ninth capacitor is electrically connected to the second terminal of the seventh resistor;

[0058] The eighth resistor has its first end electrically connected to the second end of the ninth capacitor, and the second end of the eighth resistor is electrically connected to the first end of the eighth capacitor.

[0059] The ninth resistor has its first end electrically connected to the second input terminal of the comparator and its second end electrically connected to the output terminal of the reference voltage circuit.

[0060] Optionally, the reference voltage circuit includes:

[0061] The tenth resistor, the first end of which is electrically connected to an external voltage source;

[0062] The eleventh resistor has its first end electrically connected to the second end of the tenth resistor, and its second end electrically connected to the second input terminal of the feedback signal processing circuit.

[0063] The twelfth resistor has its first end electrically connected to the second end of the eleventh resistor, and its second end is grounded.

[0064] A reference voltage regulator, wherein the cathode of the reference voltage regulator is electrically connected to the second terminal of the tenth resistor, the anode of the reference voltage regulator is grounded, and the reference terminal of the reference voltage regulator is electrically connected to the second terminal of the tenth resistor.

[0065] Optionally, it further includes a timing control circuit, the output of which is electrically connected to the output of the reference voltage circuit. The timing control circuit receives external control signals and controls the output voltage of the reference voltage circuit according to the external control signals.

[0066] The timing control circuit includes:

[0067] The thirteenth resistor, the first end of which is electrically connected to the input voltage source;

[0068] The second MOSFET has its first terminal electrically connected to the second terminal of the thirteenth resistor, its second terminal grounded, and its third terminal used to receive external control signals.

[0069] The third MOS transistor has its first terminal electrically connected to the second input terminal of the feedback signal processing circuit, its second terminal grounded, and its third terminal electrically connected to the second terminal of the thirteenth resistor.

[0070] In the technical solution provided by this utility model, the input voltage is adjusted to the first target voltage through the input voltage regulation circuit of the switching power supply structure, and then the first target voltage is adjusted to the second target voltage through the control execution circuit, the reference voltage circuit and the feedback signal processing circuit, so that the final output voltage can simultaneously meet the output requirements of low ripple and high current. Attached Figure Description

[0071] Figure 1 This is a schematic diagram of the power supply circuit according to an embodiment of the present invention;

[0072] Figure 2 This is a schematic diagram of the input voltage regulation circuit of the power supply circuit according to another embodiment of the present invention;

[0073] Figure 3This is a schematic diagram of the control and execution circuit of the power supply circuit according to another embodiment of the present invention;

[0074] Figure 4 This is a schematic diagram of the output filter circuit of the power supply circuit according to another embodiment of the present invention;

[0075] Figure 5 This is a schematic diagram of the feedback signal processing circuit of the power supply circuit according to another embodiment of the present invention;

[0076] Figure 6 This is a schematic diagram of a reference power supply circuit for another embodiment of the present invention.

[0077] Figure 7 This is a schematic diagram of a power supply circuit with a timing control circuit in another embodiment of the present invention;

[0078] Figure 8 This is a schematic diagram of the timing control circuit of the power supply circuit according to another embodiment of the present invention. Detailed Implementation

[0079] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0080] This utility model embodiment provides a power supply circuit, such as Figure 1 As shown, it includes:

[0081] An input voltage regulation circuit, which adopts a switching power supply structure, is used to adjust the input voltage to a first target voltage.

[0082] A control execution circuit, wherein the input terminal of the control execution circuit is electrically connected to the output terminal of the input voltage regulation circuit, and the control execution circuit is used to adjust the first target voltage to the second target voltage;

[0083] An output filtering circuit, wherein the input terminal of the output filtering circuit is electrically connected to the output terminal of the control execution circuit, and the output filtering circuit is used to filter the second target voltage;

[0084] A feedback signal processing circuit is included, with its output electrically connected to the control terminal of the control execution circuit. The first input terminal of the feedback signal processing circuit is electrically connected to both its output terminal and the output terminal of the output filter circuit. This feedback signal processing circuit is used to feed back the comparison signal between the second target voltage and the reference voltage, and to feed back the comparison signal between the voltage at the output terminal of the feedback signal processing circuit and the reference voltage.

[0085] A reference voltage circuit is provided, which adopts a linear power supply structure. The output terminal of the reference voltage circuit is electrically connected to the second input terminal of the feedback signal processing circuit. The reference voltage circuit is used to output a reference voltage.

[0086] In the technical solution provided by this utility model embodiment, the input voltage is adjusted to a first target voltage through the input voltage regulation circuit of the switching power supply structure. Then, through the control execution circuit, the reference voltage circuit, and the feedback signal processing circuit, the first target voltage is adjusted to a second target voltage, thereby enabling the final output voltage to simultaneously meet the output requirements of low ripple and high current. The execution control circuit has both power energy input and control signal input. The control signal adjusts the output of power energy through the execution control circuit to keep the output voltage at the set value. For the feedback signal processing circuit, there are two feedback signals. One feedback signal comes from the power energy output of the output filter circuit and is used to transmit the second target voltage to the feedback signal processing circuit, which is the basis for keeping the second output voltage stable. The other feedback signal comes from the control signal output of the feedback signal processing circuit. It is used to avoid a step when the second output voltage is powered on, which could damage the downstream load, and to speed up the response speed of the feedback signal processing circuit, thereby enhancing the performance of reducing the ripple of the second target voltage. Under the combined action of the two feedback signals, large ripple in the output voltage can be avoided.

[0087] As an optional implementation method, such as Figure 2 As shown, the input voltage regulation circuit includes:

[0088] A synchronous buck converter chip, wherein the input terminal of the synchronous buck converter chip is electrically connected to an input voltage source;

[0089] The first inductor L1, the first end of the first inductor L1 is electrically connected to the switch pin of the synchronous buck converter chip;

[0090] The first resistor R1, the first end of the first resistor R1 is electrically connected to the feedback pin of the synchronous buck converter chip;

[0091] The second resistor R2 has its first end electrically connected to the second end of the first resistor R1, and its second end is electrically connected to the second end of the first inductor L1.

[0092] The third resistor R3 has its first end electrically connected to the first end of the first resistor R1, and its second end electrically connected to the resistor ground pin of the synchronous buck converter chip.

[0093] A first capacitor C1 is connected at its first end to the second end of the second resistor R2, and the second end of the first capacitor C1 is grounded; the first end of the first capacitor C1 is used to output a first target voltage.

[0094] The second capacitor C2 has its first terminal electrically connected to the first terminal of the first capacitor C1, and its second terminal grounded.

[0095] The third capacitor C3 has its first terminal electrically connected to the first terminal of the second capacitor C2, and its second terminal grounded.

[0096] The fourth resistor R4 has its first end electrically connected to the second end of the third resistor R3, and its second end grounded.

[0097] Bootstrap capacitor C21, the first end of which is electrically connected to the switching pin of the synchronous buck converter chip;

[0098] The bootstrap resistor R21 has its first end electrically connected to the bootstrap pin of the synchronous buck converter chip, and its second end electrically connected to the second end of the bootstrap capacitor C21.

[0099] Grounding resistor R22, the first end of which is electrically connected to the first end of the first inductor L1;

[0100] Grounding capacitor C22, the first end of which is electrically connected to the second end of grounding resistor R22, and the second end of grounding capacitor C22 is grounded.

[0101] In some embodiments, the input voltage regulator circuit is used to adjust the input voltage to the optimal operating voltage value of the subsequent circuits, so that the entire power supply circuit can adapt to different input voltages. In this embodiment, a switching power supply structure is adopted, which makes full use of the wide input voltage characteristics of the switching power supply, ensuring that the entire power supply circuit can adapt to common 5V to 36V DC voltage inputs. The output voltage of the input voltage regulator circuit can be set to, for example, 1.1V.

[0102] As an optional implementation, continue as follows Figure 2 As shown, the input voltage regulation circuit further includes an input filtering module, which includes:

[0103] A filter bead FB, wherein the first terminal of the filter bead FB is electrically connected to the input voltage source;

[0104] The first filter capacitor C31 has its second terminal electrically connected to the first terminal of the filter bead FB, and its second terminal is grounded.

[0105] The second filter capacitor C32 has its first terminal electrically connected to the first terminal of the first filter capacitor C31, and its second terminal grounded.

[0106] The third filter capacitor C33 has its first terminal electrically connected to the first terminal of the second filter capacitor C32, and its second terminal grounded.

[0107] The fourth filter capacitor C34 is electrically connected to the first terminal of the third filter capacitor C33 and to the input terminal of the synchronous buck converter chip. The second terminal of the third filter capacitor C33 is grounded.

[0108] As an optional implementation, the input voltage regulation circuit further includes a first peripheral module, the first peripheral module comprising:

[0109] The first peripheral resistor R41 has its first end electrically connected to the internal voltage pin of the synchronous buck converter chip, and its second end electrically connected to the drive decoupling input pin of the synchronous buck converter chip.

[0110] The first peripheral capacitor C41 has its first terminal electrically connected to the first terminal of the first peripheral resistor R41, and its second terminal grounded.

[0111] The second peripheral capacitor C42 has its first terminal electrically connected to the second terminal of the first peripheral resistor R41, and its second terminal grounded.

[0112] The third peripheral capacitor C43 has its first terminal electrically connected to the soft-start input pin of the synchronous buck converter chip, and its second terminal grounded.

[0113] The second peripheral resistor R42 has its first end electrically connected to the valley current setting pin of the synchronous buck converter chip, and its second end grounded.

[0114] The third peripheral resistor R43 has its first end electrically connected to the operation mode selection pin of the synchronous buck converter chip, and its second end electrically connected to the first end of the first peripheral resistor R41.

[0115] The fourth peripheral resistor R44 has its first end electrically connected to the protection mode selection pin of the synchronous buck converter chip, and its second end electrically connected to the second end of the third peripheral resistor R43.

[0116] As an optional implementation, continue as follows Figure 2 As shown, the input voltage regulation circuit further includes a second peripheral module, which includes:

[0117] The fifth peripheral resistor R45, the first end of which is electrically connected to the operation signal transmission pin of the synchronous buck converter chip;

[0118] The sixth peripheral resistor R46 has its first end electrically connected to the operating signal receiving pin of the synchronous buck converter chip, and its second end electrically connected to the second end of the fifth peripheral resistor R45.

[0119] The seventh peripheral resistor R47 has its first end electrically connected to the current sensing output pin of the synchronous buck converter chip, and its second end electrically connected to the feedback pin of the synchronous buck converter chip.

[0120] The eighth peripheral resistor R48 has its first end electrically connected to the internal slope compensation selection pin of the synchronous buck converter chip, and its second end grounded.

[0121] The ninth peripheral resistor R49 has its first end electrically connected to the switching frequency pin of the synchronous buck converter chip, and its second end grounded.

[0122] As an optional implementation method, such as Figure 3 As shown, the control execution circuit includes:

[0123] The first MOSFET Q1 has its first terminal electrically connected to the first terminal of the first capacitor C1, and its second terminal is used to output the second target voltage.

[0124] The fourth capacitor C4 has its first terminal electrically connected to the first terminal of the first MOS transistor Q1, and its second terminal grounded.

[0125] The fifth capacitor C5 has its first terminal electrically connected to the first terminal of the fourth capacitor C4, and its second terminal grounded.

[0126] The fifth resistor R5 has its first end electrically connected to the third end of the first MOS transistor Q1, and its second end grounded.

[0127] The sixth resistor R6 has its first end electrically connected to the first end of the fifth resistor R5, and its second end serves as the control terminal of the control execution circuit. The second end of the sixth resistor R6 is also electrically connected to the output terminal of the feedback signal processing circuit.

[0128] In some embodiments, the control execution circuit consists of a switching transistor Q1 and its peripheral circuitry. The control execution circuit and the feedback signal processing circuit cooperate to stabilize the output voltage according to the principle of negative feedback control. The working principle of voltage stabilization is as follows: the feedback signal processing circuit compares the output voltage of the output filter circuit with the voltage provided by the reference voltage circuit, for example, 0.9V, based on the voltage feedback from the output filter circuit. When the output voltage is higher than the precise 0.9V, the switching transistor transitions from a closed conducting state to a cutoff state. This state transition consumes the portion of the voltage exceeding 0.9V, causing the output voltage of the output filter circuit to decrease towards 0.9V. When the output voltage is lower than 0.9V, the switching transistor transitions from a cutoff state to a conducting state. After the transition, the input voltage of 1.1V is directly connected to the output filter circuit, charging the output filter circuit and causing the output voltage to rise towards 0.9V. The feedback signal processing circuit continuously controls the switching transistor Q1 to turn on and off, ultimately stabilizing the output voltage of the output filter circuit at 0.9V.

[0129] As an optional implementation method, such as Figure 4 As shown, the output filter circuit includes:

[0130] The sixth capacitor C6 has its first terminal electrically connected to the second terminal of the first MOS transistor Q1, and its second terminal grounded.

[0131] The seventh capacitor C7 has its first terminal electrically connected to the first terminal of the sixth capacitor C6, and its second terminal grounded.

[0132] The eighth capacitor C8 has its first terminal electrically connected to the first terminal of the seventh capacitor C7, and its second terminal grounded. The first terminal of the eighth capacitor C8 is used to output the filtered second target voltage.

[0133] In some embodiments, an output filter circuit is required to control the output voltage ripple at a low level. Without an output filter circuit, the output voltage fluctuation of the control circuit will still have a large value, which cannot meet the application requirements for low ripple. Adding an output filter circuit can effectively filter out the AC component in the voltage fluctuation, making the output voltage more stable.

[0134] As an optional implementation method, such as Figure 5 As shown, the feedback signal processing circuit includes:

[0135] Comparator U1, the output terminal of which is electrically connected to the second terminal of the sixth resistor R6; the first input terminal of comparator U1 serves as the first input terminal of the feedback signal processing circuit, and the second input terminal of comparator U1 serves as the second input terminal of the feedback signal processing circuit;

[0136] The seventh resistor R7 has its first end electrically connected to the output terminal of the comparator U1, and its second end electrically connected to the first input terminal of the comparator U1.

[0137] The ninth capacitor C9 has its first terminal electrically connected to the first terminal of the seventh resistor R7, and its second terminal electrically connected to the second terminal of the seventh resistor R7.

[0138] The eighth resistor R8 has its first end electrically connected to the second end of the ninth capacitor C9, and the second end of the eighth resistor R8 is electrically connected to the first end of the eighth capacitor C8.

[0139] The ninth resistor R9 has its first end electrically connected to the second input terminal of the comparator U1, and its second end electrically connected to the output terminal of the reference voltage circuit.

[0140] In some embodiments, the feedback signal processing circuit determines the operating state of the switching transistor during voltage stabilization. Simultaneously, since the output voltage of the pre-amplifier voltage regulation circuit can be adjusted according to design requirements, there is no limitation on the minimum voltage difference of a linear power supply. This means that for the same output current, the power consumed by the control circuit is much less than that of an integrated linear power supply chip, effectively avoiding the shortcomings of integrated linear power supply chips. To avoid a voltage step problem during power-up, two feedback signals are used. The first feedback signal introduces the output of the feedback signal processing circuit into its first input terminal, and the second feedback signal introduces the output voltage of the output filter circuit into its first input terminal. When the circuit is powered on, before the output voltage is established, the feedback signal processing circuit, based on the first feedback signal, outputs a control to shut down the control execution circuit, isolating the voltage regulation output circuit from the subsequent output and preventing the output voltage from powering on along with the voltage regulation output circuit, thus avoiding an overshoot step in the output voltage. At the same time, when the two feedback signals work together, the first feedback signal can adjust the gain and phase response of the entire feedback loop, which enables the feedback signal processing circuit to respond to the signal of the second feedback signal at a faster speed, thereby improving the control performance of the circuit of the present invention.

[0141] As an optional implementation method, such as Figure 6 As shown, the reference voltage circuit includes:

[0142] The tenth resistor R10, the first end of which is electrically connected to an external voltage source;

[0143] The eleventh resistor R11, the first end of which is electrically connected to the second end of the tenth resistor R10, and the second end of which is electrically connected to the second input terminal of the feedback signal processing circuit;

[0144] The twelfth resistor R12 has its first end electrically connected to the second end of the eleventh resistor R11, and its second end is grounded.

[0145] A reference voltage regulator Q21 is provided, wherein the cathode of the reference voltage regulator Q21 is electrically connected to the second terminal of the tenth resistor R10, the anode of the reference voltage regulator Q21 is grounded, and the reference terminal of the reference voltage regulator Q21 is electrically connected to the second terminal of the tenth resistor R10.

[0146] In some embodiments, a reference voltage circuit provides a reference voltage to the feedback signal processing circuit, the magnitude of which is the same as the output voltage of the entire power supply circuit. By changing the reference voltage value, the output voltage can be adjusted to the desired value. For example, the output voltage of the reference voltage circuit can be set to 0.9V.

[0147] As an optional implementation method, such as Figure 7 As shown, it also includes a timing control circuit, the output of which is electrically connected to the output of the reference voltage circuit. The timing control circuit receives external control signals and controls the output voltage of the reference voltage circuit according to the external control signals.

[0148] like Figure 8 As shown, the timing control circuit includes:

[0149] The thirteenth resistor R13, the first end of which is electrically connected to the input voltage source;

[0150] The second MOSFET Q2 has its first terminal electrically connected to the second terminal of the thirteenth resistor R13, its second terminal grounded, and its third terminal used to receive external control signals.

[0151] The third MOSFET Q3 has its first terminal electrically connected to the second input terminal of the feedback signal processing circuit, its second terminal grounded, and its third terminal electrically connected to the second terminal of the thirteenth resistor R13.

[0152] In some embodiments, the timing control circuit provides a ready signal to the feedback signal processing circuit. When the system circuit design does not require power supply output, the timing control circuit will disconnect the output of the reference voltage circuit and output a not-ready signal itself. The feedback signal processing circuit will then shut down the control execution circuit based on the not-ready signal, resulting in no output voltage in the subsequent stage. When the system requires power supply output, the timing control circuit releases control over the reference voltage circuit, allowing the reference voltage to be input to the feedback signal processing circuit.

[0153] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A power supply circuit, characterized in that, include: An input voltage regulation circuit, which adopts a switching power supply structure, is used to adjust the input voltage to a first target voltage. A control execution circuit, wherein the input terminal of the control execution circuit is electrically connected to the output terminal of the input voltage regulation circuit, and the control execution circuit is used to adjust the first target voltage to the second target voltage; An output filtering circuit, wherein the input terminal of the output filtering circuit is electrically connected to the output terminal of the control execution circuit, and the output filtering circuit is used to filter the second target voltage; A feedback signal processing circuit is provided, wherein the output terminal of the feedback signal processing circuit is electrically connected to the control terminal of the control execution circuit, and the first input terminal of the feedback signal processing circuit is electrically connected to the output terminal of the feedback signal processing circuit and the output terminal of the output filter circuit. The feedback signal processing circuit is used to feed back the comparison signal between the second target voltage and the reference voltage, and to feed back the comparison signal between the output voltage and the reference voltage of the feedback signal processing circuit. A reference voltage circuit is provided, which adopts a linear power supply structure. The output terminal of the reference voltage circuit is electrically connected to the second input terminal of the feedback signal processing circuit. The reference voltage circuit is used to output the reference voltage.

2. The power supply circuit according to claim 1, characterized in that, The input voltage regulation circuit includes: A synchronous buck converter chip, wherein the input terminal of the synchronous buck converter chip is electrically connected to an input voltage source; The first inductor, the first end of the first inductor being electrically connected to the switching pin of the synchronous buck converter chip; The first resistor, the first end of which is electrically connected to the feedback pin of the synchronous buck converter chip; The second resistor has its first end electrically connected to the second end of the first resistor, and its second end is electrically connected to the second end of the first inductor. The third resistor has its first end electrically connected to the first end of the first resistor, and its second end electrically connected to the resistor ground pin of the synchronous buck converter chip. A first capacitor, with its first terminal electrically connected to the second terminal of the second resistor, and its second terminal grounded; the first terminal of the first capacitor is used to output a first target voltage. The second capacitor has its first terminal electrically connected to the first terminal of the first capacitor, and its second terminal grounded. The third capacitor has its first terminal electrically connected to the first terminal of the second capacitor, and its second terminal grounded. The fourth resistor has its first end electrically connected to the second end of the third resistor, and its second end is grounded. A bootstrap capacitor, the first terminal of which is electrically connected to the switching pin of the synchronous buck converter chip; A bootstrap resistor, wherein the first end of the bootstrap resistor is electrically connected to the bootstrap pin of the synchronous buck converter chip, and the second end of the bootstrap resistor is electrically connected to the second end of the bootstrap capacitor; A grounding resistor, wherein the first end of the grounding resistor is electrically connected to the first end of the first inductor; A grounding capacitor, wherein the first end of the grounding capacitor is electrically connected to the second end of the grounding resistor, and the second end of the grounding capacitor is grounded.

3. The power supply circuit according to claim 2, characterized in that, The input voltage regulation circuit further includes an input filtering module, which includes: A filter bead, wherein the first end of the filter bead is electrically connected to the input voltage source; A first filter capacitor, wherein a first terminal of the first filter capacitor is electrically connected to a second terminal of the filter bead, and the second terminal of the first filter capacitor is grounded; The second filter capacitor has its first terminal electrically connected to the first terminal of the first filter capacitor, and its second terminal grounded. The third filter capacitor has its first terminal electrically connected to the first terminal of the second filter capacitor, and its second terminal grounded. The fourth filter capacitor has its first terminal electrically connected to the first terminal of the third filter capacitor, and its first terminal electrically connected to the input terminal of the synchronous buck converter chip. The second terminal of the third filter capacitor is grounded.

4. The power supply circuit according to claim 2, characterized in that, The input voltage regulation circuit further includes a first peripheral module, which includes: The first peripheral resistor has its first end electrically connected to the internal voltage pin of the synchronous buck converter chip, and its second end electrically connected to the drive decoupling input pin of the synchronous buck converter chip. A first peripheral capacitor, wherein a first terminal of the first peripheral capacitor is electrically connected to a first terminal of the first peripheral resistor, and a second terminal of the first peripheral capacitor is grounded; The second peripheral capacitor has its first terminal electrically connected to the second terminal of the first peripheral resistor, and its second terminal is grounded. The third peripheral capacitor has its first terminal electrically connected to the soft-start input pin of the synchronous buck converter chip, and its second terminal grounded. The second peripheral resistor has its first end electrically connected to the valley current setting pin of the synchronous buck converter chip, and its second end grounded. The third peripheral resistor has its first end electrically connected to the operation mode selection pin of the synchronous buck converter chip, and its second end electrically connected to the first end of the first peripheral resistor. The fourth peripheral resistor has its first end electrically connected to the protection mode selection pin of the synchronous buck converter chip, and its second end electrically connected to the second end of the third peripheral resistor.

5. The power supply circuit according to claim 2, characterized in that, The input voltage regulation circuit further includes a second peripheral module, which includes: The fifth peripheral resistor, the first end of which is electrically connected to the operating signal transmission pin of the synchronous buck converter chip; The sixth peripheral resistor has its first end electrically connected to the operating signal receiving pin of the synchronous buck converter chip, and its second end electrically connected to the second end of the fifth peripheral resistor. The seventh peripheral resistor has its first end electrically connected to the current sensing output pin of the synchronous buck converter chip, and its second end electrically connected to the feedback pin of the synchronous buck converter chip. The eighth peripheral resistor has its first end electrically connected to the internal slope compensation selection pin of the synchronous buck converter chip, and its second end grounded. The ninth peripheral resistor has its first end electrically connected to the switching frequency pin of the synchronous buck converter chip, and its second end grounded.

6. The power supply circuit according to claim 2, characterized in that, The control execution circuit includes: The first MOSFET has its first terminal electrically connected to the first terminal of the first capacitor, and its second terminal is used to output the second target voltage. The fourth capacitor has its first terminal electrically connected to the first terminal of the first MOS transistor, and its second terminal grounded. The fifth capacitor has its first terminal electrically connected to the first terminal of the fourth capacitor, and its second terminal grounded. The fifth resistor has its first end electrically connected to the third end of the first MOS transistor, and its second end grounded. The sixth resistor has its first end electrically connected to the first end of the fifth resistor, and its second end serves as the control terminal of the control execution circuit. The second end of the sixth resistor is also electrically connected to the output terminal of the feedback signal processing circuit.

7. The power supply circuit according to claim 6, characterized in that, The output filtering circuit includes: The sixth capacitor has its first terminal electrically connected to the second terminal of the first MOS transistor, and its second terminal grounded. The seventh capacitor has its first terminal electrically connected to the first terminal of the sixth capacitor, and its second terminal grounded. The eighth capacitor has its first terminal electrically connected to the first terminal of the seventh capacitor, and its second terminal grounded. The first terminal of the eighth capacitor is used to output the filtered second target voltage.

8. The power supply circuit according to claim 7, characterized in that, The feedback signal processing circuit includes: A comparator, the output of which is electrically connected to the second terminal of the sixth resistor; the first input of the comparator serves as the first input of the feedback signal processing circuit, and the second input of the comparator serves as the second input of the feedback signal processing circuit. A seventh resistor, the first end of which is electrically connected to the output terminal of the comparator, and the second end of which is electrically connected to the first input terminal of the comparator; A ninth capacitor, wherein the first terminal of the ninth capacitor is electrically connected to the first terminal of the seventh resistor, and the second terminal of the ninth capacitor is electrically connected to the second terminal of the seventh resistor; The eighth resistor has its first end electrically connected to the second end of the ninth capacitor, and the second end of the eighth resistor is electrically connected to the first end of the eighth capacitor. The ninth resistor has its first end electrically connected to the second input terminal of the comparator and its second end electrically connected to the output terminal of the reference voltage circuit.

9. The power supply circuit according to claim 1, characterized in that, The reference voltage circuit includes: The tenth resistor, the first end of which is electrically connected to an external voltage source; The eleventh resistor has its first end electrically connected to the second end of the tenth resistor, and its second end electrically connected to the second input terminal of the feedback signal processing circuit. The twelfth resistor has its first end electrically connected to the second end of the eleventh resistor, and its second end is grounded. A reference voltage regulator, wherein the cathode of the reference voltage regulator is electrically connected to the second terminal of the tenth resistor, the anode of the reference voltage regulator is grounded, and the reference terminal of the reference voltage regulator is electrically connected to the second terminal of the tenth resistor.

10. The power supply circuit according to claim 9, characterized in that, It also includes a timing control circuit, the output of which is electrically connected to the output of the reference voltage circuit. The timing control circuit receives external control signals and controls the output voltage of the reference voltage circuit according to these signals. The timing control circuit includes: The thirteenth resistor, the first end of which is electrically connected to the input voltage source; The second MOSFET has its first terminal electrically connected to the second terminal of the thirteenth resistor, its second terminal grounded, and its third terminal used to receive external control signals. The third MOS transistor has its first terminal electrically connected to the second input terminal of the feedback signal processing circuit, its second terminal grounded, and its third terminal electrically connected to the second terminal of the thirteenth resistor.

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