Power supply circuit for computer mainboard

Abstract

The power supply circuit for the computer mainboard comprises a power supply chip, an inductor, a voltage adjusting unit and a voltage compensation unit, the power supply chip controls an SW pin of the power supply chip to output PWM signals according to high level signals received by a VIN pin and an EN pin, the inductor is used for filtering the PWM signals output by the SW pin, and the voltage adjusting unit is used for adjusting the voltage of the power supply chip according to the high level signals received by the VIN pin and the EN pin. A stable power supply signal is output; the voltage compensation unit debugs the power supply signal, so that the power supply chip outputs a stable power supply signal; the voltage adjusting unit is matched with the FB pin of the power supply chip, the output voltage of the power supply signal is adjusted according to needs, and the circuit can be suitable for computer mainboards of CPUs with different power consumptions.

Description

Technical Field

[0001] The utility model belongs to the field of circuits, and in particular relates to a power supply circuit for a computer mainboard. Background Art

[0002] The 21st century is an era of rapid development of computer technology. With the increasing technological level, both corporate office and personal life are inseparable from the application of computers. It can be said that the emergence of computer technology has brought us convenience and greatly improved personal work efficiency. Therefore, this technology has been widely used in any industry. In today's society, computers have become an indispensable key device in people's daily lives.

[0003] Most computer functions are realized through the computer motherboard, which is composed of many modules, such as CPU, graphics card, WIFI module, DDR, power module, etc. Different modules need corresponding power supplies to maintain normal operation of the module. In addition to these specific power supplies for modules, there are also some multi-function power supplies on the computer motherboard, which will supply power to multiple different places on the motherboard. For example, the power signals +V3P3A, +V5P0A, and +V1P8A will be powered on first when the computer is turned on, and then power other parts to ensure the normal startup and operation of the computer.

[0004] The input voltage of existing power chips is small and can only be used for motherboards with low-power CPUs. However, for those high-power computers, the output voltage is high, and when the adapter is connected, the output voltage of the DC power adapter or the output voltage of the Type-c adapter will directly increase the input voltage of the power supply circuit.

[0005] Based on the above reasons, there is an urgent need for a power supply circuit for a computer motherboard that can solve the above problems. Utility Model Content

[0006] The utility model aims to overcome the above-mentioned deficiencies of the prior art and provide a power supply circuit for a computer mainboard suitable for CPUs with different power consumptions.

[0007] The utility model is implemented as follows: a power supply circuit for a computer mainboard, characterized in that it comprises:

[0008] A power chip, wherein the VIN pin and the EN pin of the power chip are respectively used to be connected to the control unit, and the power chip controls the SW pin of the power chip to output a PWM signal according to the high-level signals received by the VIN pin and the EN pin;

[0009] An inductor, used for filtering the PWM signal output by the SW pin and outputting a stable power signal;

[0010] A voltage regulating unit, used to cooperate with the FB pin of the power chip to adjust the output voltage of the power signal;

[0011] The voltage compensation unit is used to debug the power signal so that the power chip outputs a stable power signal.

[0012] Specifically, the voltage regulating unit includes a first resistor and a second resistor arranged in series, one end of the first resistor is connected to the output end of the inductor, the other end of the first resistor is connected to the second resistor, the FB pin is connected to the node between the first resistor and the second resistor, and the output end of the second resistor is used to output the output voltage of the adjusted power supply signal.

[0013] Specifically, the voltage compensation unit includes a third resistor and a first capacitor arranged in series, one end of the first capacitor is connected to a node between the first resistor and the inductor, the other end of the first capacitor is connected to one end of the third resistor, and the other end of the third resistor is connected to the FB pin.

[0014] Furthermore, the PG pin of the power chip is used to receive a +V3P3A signal, and an input end of the PG pin is used to be connected to a fourth resistor that can separate the +V3P3A signal from the PG pin.

[0015] Furthermore, when the +V3P3A signal is pulled up, the PG pin outputs a high-level PG signal, and the control unit determines that the power chip has completed the work of outputting the voltage based on the received PG signal.

[0016] Furthermore, the AGND pin of the power chip is connected to the power signal, a short-circuit point is connected between the AGND pin and the PGND pin of the power chip, and the power chip is connected to the GND copper foil on the mainboard through the short-circuit point.

[0017] Furthermore, the VCC pin of the power chip is used to be connected to the input terminal of the IC chip, and is used to provide a 3.3V working power supply to the driving circuit and the control circuit inside the IC chip.

[0018] Furthermore, a VIN pin of the power chip is connected to a first filtering unit for filtering an input Vin signal.

[0019] Furthermore, the power supply circuit for the computer mainboard further includes a second filtering unit for filtering the power signal output by the power chip.

[0020] Furthermore, the power supply circuit for the computer mainboard also includes a delay unit for delaying the input EN signal.

[0021] The utility model provides a power supply circuit for a computer mainboard, comprising a power chip, an inductor, a voltage regulating unit and a voltage compensation unit, wherein the power chip controls the SW pin of the power chip to output a PWM signal according to high-level signals received by the VIN pin and the EN pin, the inductor is used to filter the PWM signal output by the SW pin and output a stable power signal; the voltage compensation unit debugs the power signal so that the power chip outputs a stable power signal; the voltage regulating unit cooperates with the FB pin of the power chip to adjust the output voltage of the power signal as needed, and can be suitable for computer mainboards with CPUs of different power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the present utility model, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 The utility model is a circuit diagram of a power supply circuit for a computer mainboard provided by an embodiment of the utility model.

[0024] Figure 2 The present invention is a schematic diagram of the pin packaging of a power chip in a power supply circuit for a computer motherboard provided by an embodiment of the present invention.

[0025] Figure 3 It is a PCB diagram of a power chip in a power supply circuit for a computer motherboard provided by an embodiment of the utility model.

[0026] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0028] In the present invention, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or state relationships based on the positions or state relationships shown in the drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific position, or to be constructed and operated in a specific position.

[0029] In addition, some of the above terms may be used to express other meanings in addition to indicating a position or state relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in this utility model can be understood according to specific circumstances.

[0030] In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0031] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components, which may be the same or different in specific types and configurations, and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0032] Overview of the power supply circuit for a computer motherboard as an example

[0033] like Figure 1 to Figure 3 As shown, an embodiment of the utility model provides a power supply circuit for a computer motherboard, characterized in that it includes:

[0034] A power chip U27, wherein the VIN pin and the EN pin of the power chip U27 are respectively used to connect to a control unit (not shown), and the power chip U27 controls the SW pin of the power chip U27 to output a PWM signal according to the high-level signals received by the VIN pin and the EN pin;

[0035] The inductor LP32 is used to filter the PWM signal output by the SW pin and output a stable power signal. In this embodiment, the power signal is a +V1P8A signal;

[0036] The voltage regulating unit 100 is used to cooperate with the FB pin of the power chip U27 to adjust the output voltage of the power signal, and can be applied to computer motherboards with CPUs of different power consumption;

[0037] The voltage compensation unit 200 is used to debug the power signal so that the power chip U27 outputs a stable power signal.

[0038] Specifically, the voltage regulating unit 100 includes a first resistor RP601 and a second resistor RP602 arranged in series, one end of the first resistor RP601 is connected to the output end of the inductor LP32, the other end of the first resistor RP601 is connected to the second resistor RP602, the FB pin is connected to the node between the first resistor RP601 and the second resistor RP602, and the output end of the second resistor RP602 is used to output the output voltage of the adjusted power supply signal.

[0039] In this embodiment, when the VIN pin and the EN pin of the power chip U27 receive a high-level signal, the circuit starts to work, and then the SW pin of the power chip U27 will send out a PWM (Pulse Width Modulation) signal, which will output a stable power signal (+V1P8A signal) after passing through the inductor LP32; at the same time, the power supply voltage (+V1P8A) can be determined based on the 10th PIN (FB) of the power chip U27 and the resistors RP601 and RP602. The formula of power supply voltage (+V1P8A) = voltage at the FB pin (VFB) * (resistor RP601 + resistor RP602) / resistor RP602 can be used to adjust the output voltage of the power signal as needed.

[0040] Specifically, the voltage compensation unit 200 includes a third resistor RP600 and a first capacitor CP447 arranged in series, one end of the first capacitor CP447 is connected to the node between the first resistor RP601 and the inductor LP32, the other end of the first capacitor CP447 is connected to one end of the third resistor RP600, and the other end of the third resistor RP600 is connected to the FB pin. The third resistor RP600 and the first capacitor CP447 form a compensation circuit for the power supply signal. When the power supply output signal is not very stable, it can be debugged through the compensation circuit to output a stable signal.

[0041] Furthermore, the PG pin of the power chip is used to receive a +V3P3A signal, and the input end of the PG pin is used to connect to a fourth resistor RP1486 that can separate the +V3P3A signal from the PG pin; the fourth resistor RP1486 has a relatively large resistance, generally 100K Ohm, which can separate the +V3P3A signal from the PG PIN pin to prevent the +V3P3A signal from being pulled down when the PG PIN pin is at a low level, thereby affecting the operation of the mainboard.

[0042] Furthermore, when the +V3P3A signal is pulled up, the PG pin outputs a high-level PG signal, and the control unit determines that the power chip has completed the work of outputting the voltage based on the received PG signal. In this embodiment, the function of the PG pin of the power chip U27 is as follows: when the power chip U27 successfully outputs the power signal (+V1P8A signal), the PG pin, when the +V3P3A signal is pulled up, will output a high-level signal connected to the control unit (EC module), notifying the control unit that the power chip U27 has completed the work and the system can proceed to the next step; at the same time, the PG signal can also be used as an enable signal for other power modules to control the power-on timing of different power signals to meet the CPU's requirements for power-on timing.

[0043] Furthermore, the AGND pin of the power chip U27 is connected to the power signal, and a short-circuit point is connected between the AGND pin and the PGND pin of the power chip U27, and the power chip U27 is connected to the GND copper foil on the mainboard through the short-circuit point. In this embodiment, the output signal (AGND_V1P8A signal) of the power chip U27 is connected to the AGND pin of the power chip U27 to serve as the signal GND copper foil of the power chip U27. The GND copper foil is an independent copper plating and will not be interfered by other sensitive signals, and is connected to the entire GND copper foil on the mainboard through the short-circuit point SP33.

[0044] Furthermore, the VCC pin of the power chip U27 is used to connect to the input end of the IC chip, and is used to provide a 3.3V working power supply to the drive circuit and control circuit inside the IC chip. In this embodiment, the VCC pin of the power chip U27 is a 3.3V power supply signal output from the inside of the IC, which can be used for the working power supply of the drive circuit and control circuit inside the IC. The load capacity of this power supply signal is relatively weak, so it is not connected to other modules for use, but is only used for the internal circuit of the IC itself. The capacitor CP560 is a filter capacitor for the 3.3V power supply signal, which can filter out interference signals and ensure its stability.

[0045] Furthermore, the VIN pin of the power chip U27 is connected to a first filtering unit 300 for filtering the input Vin signal. In this example, the first filtering unit 300 includes a plurality of second capacitors CP513, third capacitors CP514, fourth capacitors CP515 and fifth capacitors CP517 arranged in parallel. One ends of the second capacitor CP513, the third capacitor CP514, the fourth capacitor CP515 and the fifth capacitor CP517 are respectively connected to the VIN pin, and the other ends are grounded. The second capacitor CP513, the third capacitor CP514, the fourth capacitor CP515 and the fifth capacitor CP517 are filter capacitors for the Vin signal of the power chip U27, which can filter out interference signals in the external Vin signal to keep it clean and stable.

[0046] Furthermore, the power supply circuit for the computer motherboard also includes a second filtering unit 400 for filtering the power signal output by the power chip U27, and the second filtering unit 400 includes a plurality of sixth capacitors CP564, seventh capacitors CP565 and eighth capacitors CP566 arranged in parallel, and one ends of the sixth capacitor CP564, the seventh capacitor CP565 and the eighth capacitor CP566 are respectively connected to the inductor LP32, and the other ends are grounded; in this embodiment, the sixth capacitor CP564, the seventh capacitor CP565 and the eighth capacitor CP566 are filter capacitors for the output signal +V1P8A of the power chip U27, which can filter out interference signals in +V1P8A to keep it in a clean and stable state.

[0047] Furthermore, the power supply circuit for the computer motherboard also includes a delay unit 500 for delaying the input EN signal. The delay unit 500 includes a ninth capacitor CP655 and a fifth resistor RP76 arranged in parallel. In this embodiment, the ninth capacitor CP655 and the fifth resistor RP76 constitute a delay circuit for the EN signal of the power chip U27. The delay time can be adjusted by changing their resistance and capacitance as needed to meet the power-on timing requirements of the power chip U27. The sixth resistor RP1463 is arranged in parallel with the ninth capacitor CP655 and connected to the EN pin. The sixth resistor RP1463 is a voltage-stabilizing resistor, which plays a role in voltage stabilization.

[0048] In this embodiment, the seventh resistor RP1488 and the tenth capacitor CP446 constitute the BOOST unit 600 of the power chip U27. The BOOST unit 600 can raise the PWM level signal output by the power chip U27 as a whole and convert it into the UGATE drive signal of the switching MOSFET of the power chip U27, which has the same frequency and phase as the PWM signal, and the same frequency and anti-phase as the LGATE signal. The three together constitute the switching signal of the power chip U27, and through the alternating switching of the three, the inductor LP32 is switched back and forth between the charging and discharging states, thereby realizing the conduction or cutoff of the power signal (+V1P8A signal) of the power chip U27.

[0049] like Figure 2 As shown, in this example, preferably, the outer package size of the power chip U27 is 2mm*2mm, and the overall size is small, which can effectively save the space occupied by the circuit and is beneficial to the overall layout and wiring of the motherboard.

[0050] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the protection scope of the present invention.

Claims

1. A power supply circuit for a computer motherboard, characterized in that: include: A power chip, wherein the VIN pin and the EN pin of the power chip are respectively used to be connected to the control unit, and the power chip controls the SW pin of the power chip to output a PWM signal according to the high-level signals received by the VIN pin and the EN pin; An inductor, used for filtering the PWM signal output by the SW pin and outputting a stable power signal; A voltage regulating unit, used to cooperate with the FB pin of the power chip to adjust the output voltage of the power signal; The voltage compensation unit is used to debug the power signal so that the power chip outputs a stable power signal.

2. The power supply circuit for a computer motherboard according to claim 1, characterized in that: The voltage regulating unit includes a first resistor and a second resistor arranged in series, one end of the first resistor is connected to the output end of the inductor, the other end of the first resistor is connected to the second resistor, the FB pin is connected to the node between the first resistor and the second resistor, and the output end of the second resistor is used to output the output voltage of the adjusted power supply signal.

3. The power supply circuit for a computer motherboard according to claim 2, characterized in that: The voltage compensation unit includes a third resistor and a first capacitor arranged in series, one end of the first capacitor is connected to a node between the first resistor and the inductor, the other end of the first capacitor is connected to one end of the third resistor, and the other end of the third resistor is connected to the FB pin.

4. The power supply circuit for a computer motherboard according to claim 1, characterized in that: The PG pin of the power chip is used to receive a +V3P3A signal, and an input end of the PG pin is used to be connected to a fourth resistor that can separate the +V3P3A signal from the PG pin.

5. The power supply circuit for a computer mainboard according to claim 4, characterized in that: When the +V3P3A signal is pulled up, the PG pin outputs a high-level PG signal, and the control unit determines that the power chip has completed the work of outputting the voltage based on the received PG signal.

6. The power supply circuit for a computer mainboard according to claim 1, characterized in that: The AGND pin of the power chip is connected to the power signal, a short-circuit point is connected between the AGND pin and the PGND pin of the power chip, and the power chip is connected to the GND copper foil on the mainboard through the short-circuit point.

7. The power supply circuit for a computer mainboard according to claim 1, characterized in that: The VCC pin of the power chip is used to connect to the input end of the IC chip, and is used to provide a 3.3V working power supply to the driving circuit and the control circuit inside the IC chip.

8. The power supply circuit for a computer mainboard according to claim 1, characterized in that: The VIN pin of the power chip is connected to a first filtering unit for filtering an input Vin signal.

9. The power supply circuit for a computer motherboard according to claim 1, characterized in that: It also includes a second filtering unit for filtering the power signal output by the power chip.

10. The power supply circuit for a computer mainboard according to claim 1, characterized in that: The invention also comprises a delay unit for delaying the input EN signal.

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