TWI399922B - Power supply system for motherboard - Google Patents

Description

Motherboard power supply system

The invention relates to a power supply circuit for a motherboard, in particular to a power supply system for conveniently removing CMOS data in a south bridge chip on a computer motherboard.

The power supply circuit on the computer motherboard usually uses jumpers to clear the CMOS data in the south bridge chip or restore the BIOS settings, so that the user can start the computer when the CMOS password is forgotten or the BIOS setting cannot start the computer. The most common type on a computer motherboard is a keycap jumper. The keycap jumper consists of a base and a keycap. A plurality of pins that are not connected are disposed on the base of the jumper, and the adjacent two pins are electrically connected through the jumper of the jumper to achieve a specific connection relationship. In the normal working condition of the computer, the key cap is installed between the two specific pins on the base to realize the normal power supply of the south bridge chip by the power supply circuit, and the CMOS data in the south bridge chip is not lost. When the computer settings fail, the user can remove the keycap from the base and install it between the other two pins to clear the CMOS data in the south bridge chip. This requires disassembling the chassis, finding the location of the jumper to clear the CMOS data, and then performing the jumper operation, which brings great inconvenience to the user.

In view of the above, it is necessary to provide a motherboard power supply system, which is convenient for the user to clear the CMOS data in the south bridge chip.

A motherboard power supply system includes a power supply circuit for supplying power to a south bridge chip and a control circuit, wherein an input end of the power supply circuit is connected to a power supply, and an output end of the power supply circuit is connected to one of the reset ends of the south bridge chip, the control The circuit includes a first transistor and a second transistor, the first end of the first transistor is configured to receive a control signal of the south bridge chip, and the first end of the second transistor is coupled to the first transistor The second end of the second transistor is connected to the re-set end of the south bridge chip, and the third ends of the first and second transistors are grounded. When the motherboard is working normally, the control signal is in the first logic state. The second end of the second transistor is at a high level. When the CMOS data of the motherboard needs to be cleared, the control signal is in a second logic state, so that the second end of the second transistor and the re-set end of the south bridge chip Low level to clear the CMOS data of the motherboard.

The motherboard power supply system provides continuous power supply to the south bridge chip through the power supply circuit, and controls the turn-on and turn-off of the two transistors through the control signal of the south bridge chip to clear the CMOS data, thereby avoiding cumbersome steps such as opening the chassis, The user brings convenience.

10‧‧‧Power circuit

V‧‧‧DC power supply

20‧‧‧Filter circuit

Q1, Q2‧‧‧ MOSFET

40‧‧‧jumper

RTCRST‧‧‧Reposition

C1, C2‧‧‧ capacitor

Vcc‧‧‧Power supply

D1‧‧‧Schottky diode

30‧‧‧Control circuit

GPIO_CLRCMOS‧‧‧ pin

41-43‧‧‧ Pin

R1-R4‧‧‧ resistance

1 is a circuit diagram of a preferred embodiment of a power supply system for a motherboard of the present invention.

Referring to FIG. 1, the motherboard power supply system of the present invention is used to supply power to the south bridge chip on the computer motherboard, ensuring that the CMOS (Complementary Metal Oxide Semiconductor) data in the south bridge chip is not lost due to power failure, and the user needs to recover the computer. It is easy to clear CMOS data when setting. The host A preferred embodiment of the board power supply system includes a power circuit 10, a filter circuit 20, a control circuit 30, and a jumper 40. The jumper 40 has three pins 41, 42 and 43 through which the power circuit 10 passes. The filter circuit 20 supplies power to the south bridge chip. The power supply circuit 10 is further connected to the pin 42 of the jumper 40 through the filter circuit 20. The pin 41 of the jumper 40 is grounded, and the pin 43 of the jumper 40 is suspended. A pin 42 of the jumper 40 is connected to one of the south bridge wafers RTCRST.

The power supply circuit 10 includes a Schottky diode D1, a resistor R1 and a DC power supply V. The Schottky diode D1 includes a first anode 1, a second anode 2 and a cathode 3. The Schottky II The first anode 1 of the polar body D1 is connected to a power supply Vcc, and the second anode 2 is connected to the direct current power supply V through a resistor R1. The cathode 3 of the Schottky diode D1 is connected to the input end of the filter circuit 20.

The filter circuit 20 includes a resistor R2 and capacitors C1 and C2. One end of the capacitor C1 serves as an input end of the filter circuit 2, and is connected to the cathode of the Schottky diode D1, and is also grounded through a resistor R2 and a capacitor C2 connected in series. The connection node of the resistor R2 and the capacitor C2 serves as the filter. The output of circuit 20 is connected to pin 42 of jumper 40.

The control circuit 30 includes two MOS (Metal Oxide Semiconductor) field effect transistors (MOSFETs) Q1 and Q2, and resistors R3 and R4. The MOSFETs Q1 and Q2 are N-channel MOSFETs, and the gate of the MOSFET Q1 serves as the control. The input end of the circuit 30 is connected to one of the general-purpose input/output port (GPIO) pins GPIO_CLRCMOS of the south bridge chip, and the gate of the MOSFET Q1 is also connected to the power supply Vcc through the resistor R3, and the drain of the MOSFET Q1 is connected to the gate Gate of MOSFET Q2, the gate of MOSFET Q2 is connected through resistor R4 Connected to the power supply Vcc, the drain of the MOSFET Q2 serves as the output end of the control circuit 30, and is connected to the connection node of the resistor R2 and the capacitor C2. The sources of the MOSFETs Q1 and Q2 are both grounded. The GPIO can be controlled by programming the BIOS. In other embodiments, the MOSFETs Q1 and Q2 may also be NPN (Negative-Positive-Negative) type transistors. The base, collector and emitter of the NPN transistor are connected to the gate and the MOSFET respectively. The connection between the pole and the source is the same.

When the computer is working normally, the power supply Vcc transmits power to the re-terminal RTCRST of the south bridge chip through the Schottky diode D1 output power, and supplies power to the south bridge chip. When the computer mainframe is powered off, the power supply Vcc has no output. The power supply V is powered by the resistor R1 and the Schottky diode D1 to supply power to the south bridge chip. The filter circuit 20 can filter out the clutter generated during the power signal transmission process, and eliminate the influence of the clutter signal on the south bridge chip. Omitted.

When the computer is working normally, the pin 42 of the jumper 40 is connected to the pin 43 through a keycap. The GPIO pin GPIO_CLRCMOS exhibits a high impedance state, the MOSFET Q1 is turned on, the MOSFET Q2 is turned off, and the drain of the MOSFET Q2 is high. Level. When the user needs to clear the CMOS data in the south bridge chip, the jumper can be removed by re-installing on the pins 41 and 42 to make the pin 42 grounded to a low level to clear the south bridge chip. CMOS data; can also enter the BIOS, modify the BIOS setting of the GPIO pin GPIO_CLRCMOS level, so that the GPIO pin GPIO_CLRCMOS is low, so that MOSFET Q1 is turned off, MOSFET Q2 is turned on, MOSFET Q2 is bungee Presenting a low level, causing the re-terminal RTCRST of the south bridge wafer to be low to clear the south bridge wafer CMOS data, you can further set the hotkey on the computer keyboard to directly start the BIOS to control the GPIO_CLRCMOS level setting of the GPIO pin.

The power supply system of the motherboard of the invention not only retains the manner of using the jumper to clear the CMOS data in the south bridge chip, but also allows the user to select the hot key mode, thereby avoiding the need to clear the CMOS data in the south bridge chip, and unpacking the chassis, bringing the user Convenience.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

10‧‧‧Power circuit

V‧‧‧DC power supply

20‧‧‧Filter circuit

Q1, Q2‧‧‧ MOSFET

40‧‧‧jumper

RTCRST‧‧‧Reposition

C1, C2‧‧‧ capacitor

Vcc‧‧‧Power supply

D1‧‧‧Schottky diode

30‧‧‧Control circuit

GPIO_CLRCMOS‧‧‧ pin

41-43‧‧‧ Pin

R1-R4‧‧‧ resistance

Claims (7)

A motherboard power supply system includes a power supply circuit for supplying power to a south bridge chip and a control circuit, wherein an input end of the power supply circuit is connected to a power supply, and an output end of the power supply circuit is connected to one of the reset ends of the south bridge chip, the control The circuit includes a first transistor and a second transistor, the first end of the first transistor is configured to receive a control signal of the south bridge chip, and the first end of the second transistor is coupled to the first transistor The second end of the second transistor is connected to the re-set end of the south bridge chip, and the third ends of the first and second transistors are grounded. When the motherboard is working normally, the control signal is in the first logic state. The second end of the second transistor is at a high level. When it is required to clear the CMOS (Complementary Metal Oxide Semiconductor) data of the motherboard, the control signal is in a second logic state, so that the second end of the second transistor And the reset terminal of the south bridge chip is low to clear the CMOS data of the motherboard. The motherboard power supply system of claim 1, wherein the power circuit comprises a first resistor, a Schottky diode, and a DC power supply, the Schottky diode includes a first anode, a second anode and a cathode, the first anode of the Schottky diode is used as an input end of the power circuit, and the second anode of the Schottky diode is connected to the DC power source through the first resistor The cathode of the special base diode serves as the output of the power supply circuit. The motherboard power supply system of claim 2, further comprising a filter circuit, wherein the cathode of the Schottky diode is connected to the re-terminal of the south bridge chip through the filter circuit, the filter circuit includes a first capacitor a second capacitor and a second resistor, one end of the first capacitor is connected to the cathode of the Schottky diode, and the other end is grounded, and one end of the second capacitor is connected to the cathode of the Schottky diode through the second resistor. One end of the second capacitor is also connected to the second end of the second transistor, and the other end of the second capacitor is grounded. The motherboard power supply system of claim 3, further comprising a jumper, the jumper having a first pin, a second pin and a third pin, the second lead of the jumper The pin is connected to the second end of the second transistor, the first pin of the jumper is grounded, and the third pin of the jumper is suspended. When the power supply system of the motherboard is working normally, the first button cap is placed in the jumper On the second pin and the third pin; when the CMOS data of the south bridge chip is cleared, the key cap is placed on the second pin and the first pin of the jumper. The motherboard power supply system of claim 1, wherein the control signal is sent by one of the universal input/output ports of the south bridge chip. The motherboard power supply system of claim 1, wherein the first and second transistors are N-channel MOS (Metal Oxide Semiconductor) field effect transistors, the first, second, and third ends They are the gate, the drain and the source. The motherboard power supply system of claim 1, wherein the first and second transistors are NPN (Negative-Positive-Negative) transistors, and the first, second, and third ends are respectively Base, collector and emitter.