Patent ID: 9559599
Date: 2017-01-31
CPC Classifications: H02M,Y02B

Claim:
1. An electronic apparatus comprising: a system portion configured to operate with a received voltage; and a power supply, the power supply comprising: a pulse width modulation (PWM) generator configured to generate a PWM signal; a converter configured to transfer voltage from a primary side to a secondary side in accordance with an output voltage of the PWM generator; an output portion configured to supply voltage at the secondary side of the converter as a standby voltage to the system portion; and a controller configured to monitor the standby voltage at the secondary side of the converter and voltage of the system portion, and output a wake-up signal to the PWM generator when an external input signal is received from the system portion, wherein the PWM generator operates under an ON/OFF control mode to perform an intermittent PWM operation by receiving feedback on the standby voltage at the secondary side of the converter, the PWM signal is turned on/off in accordance with levels of the standby voltage at the secondary side, and the voltage being supplied to components, except, when the PWM signal is turned off, the voltage on the secondary side is only supplied to a component configured to monitor the feedback of the standby voltage, wherein the system portion applies the external input signal to the controller before a point of time when an output current of the power supply is varied, and, in response to the wake-up signal, the PWM generator is woken up and switched from the ON/OFF control mode to a high speed PWM mode so that the PWM generator is controlled to continuously perform the PWM operation rather than the intermittent PWM operation, and wherein the controller generates a signal for turning on the output voltage needed for the system portion in response to determining that the standby voltage is stably supplied after switching to the high speed PWM mode and the electronic apparatus is switched to a normal mode.