POWER SUPPLY CIRCUIT AND NOTEBOOK COMPUTER INCLUDING THE SAME

摘要

The disclosure provides a power supply circuit including a pulse width modulator (PWM), a first voltage conversion unit, a second voltage conversion unit, a conversion chip, and a delay unit. The first voltage conversion unit converts a voltage of a power supply to a first voltage according to pulse signals output by the PWM. The second voltage conversion unit converts the voltage of the power supply to a second voltage according to the pulse signals. The conversion chip converts the first voltage to a third voltage, converts the second voltage to a fourth voltage, and outputs a power-good signal to a south bridge chipset through the delay unit. The disclosure also provides a notebook computer including the power supply circuit.

主权项

1. A power supply circuit comprising:
a first diode comprising an anode and a cathode; a first electronic switch and a second electronic switch, each of the first electronic switch and the second electronic switch comprising a first terminal, a second terminal, and a third terminal; a pulse width modulator (PWM) configured to generate a pulse signal; a first voltage conversion unit obtaining the pulse signal from the PWM, and configured to convert a voltage of a first power supply into a first voltage according to the pulse signal outputted by PWM; a second voltage conversion unit obtaining the pulse signal from the PWM, and configured to convert the voltage of the first power supply into a second voltage according to the pulse signal outputted by PWM; a conversion chip obtaining the first voltage from the first voltage conversion unit and the second voltage from the second voltage conversion unit, and configured to convert the first voltage into a third voltage and the second voltage into a fourth voltage; and a delay unit comprising a first resistor and a first capacitor; wherein the cathode of the first diode obtains the fourth voltage from the conversion chip, the anode of the first diode obtains the third voltage from the conversion chip through the first resistor, and the anode of the first diode is electrically coupled to ground through the first capacitor, the first terminal of the first electronic switch obtains the first voltage from the first voltage conversion unit through a second resistor, the second terminal of the first electronic switch obtains a power-on signal through a third resistor, the third terminal of the first electronic switch is electrically coupled to ground; wherein the first terminal of the second electronic switch is electrically coupled to a node between the first resistor and the first capacitor, the second terminal of the second electronic switch obtains the power-on signal through a fourth resistor, the third terminal of the second electronic switch is electrically coupled to ground; the node between the first resistor and the first capacitor is configured to output a power-good signal; wherein when the power-on signal is at a high-voltage level, the first electronic switch is turned on, the second electronic switch is turned on, the node between the first resistor and the first capacitor outputs the power-good signal at a low-voltage level; and wherein when the power-on signal is at a low-voltage level, the first electronic switch is turned off, the second electronic switch is turned off, the first diode is turned off, the node between the first resistor and the first capacitor outputs the power-good signal at a high-voltage level.