Chengdu Monolithic Power Systems Co., Ltd.

Hangzhou Mps Semiconductor Technology Ltd.

Guangzhuo Li

Siran Wang

Pengfei Liu

Hui Li

Zilin Fan

An over-current protection circuit has a current sensing circuit, an over-current comparing circuit, an isolation circuit and a control circuit. The current sensing circuit generates a current sensing signal based on a current flowing through an inductor of a voltage converter. The over-current comparing circuit receives the current sensing signal and generates a first over-current indication signal based on the current sensing signal. The isolation circuit receives the first over-current indication signal and generates a second over-current indication signal based on the first over-current indication signal. The control circuit receives the second over-current indication signal, and generates a control signal to control a switch of the voltage converter. The control circuit turns off the switch when the second over-current indication signal indicates that an over-current condition occurs.

Voltage converter with over-current protection and over-current protection method thereof

A totem pole PFC (Power Factor Correction) circuit, having: a first switch, a second switch and a control circuit. When the totem pole PFC circuit works in CCM (Continuous Current Mode), the control circuit is configured to turn on a main switch when a current detecting signal indicative of an AC input current of the totem pole PFC circuit decreases to a current valley reference signal, and keep the main switch ON for a first on-time period. When the totem pole PFC circuit works in DCM (Discontinuous Current Mode), the control circuit is configured to turn on the main switch at a valley of a switching voltage after expiry of a time delay started from when the AC input current decreases to zero, and keep the main switch ON for a second on-time period.

Control circuit for a totem pole power factor correction circuit and the method thereof

A circuit for controlling a switching mode power supply having a power switch, having: a feedback pulse circuit, configured to receive a feedback signal, and to provide a feedback pulse signal; a load determining circuit, configured to receive the feedback signal, and to provide a load determining signal; a light load pulse circuit, configured to receive the load determining signal and a frequency regulating signal, and to provide a light load pulse signal; a frequency regulating circuit, configured to receive the load determining signal, the light load pulse signal and a normal load pulse signal, and to provide the frequency regulating signal; and a selecting circuit, configured to receive the load determining signal, the feedback pulse signal and the light load pulse signal, and to provide an on control signal and the normal load pulse signal; wherein the on control signal controls an on operation of the power switch.

Circuit for controlling a switching mode power supply and the method thereof

A control circuit and control method for an interleaved switching converter having a first and second interleaved voltage regulating circuit. The control method is: controlling a first switch of the first voltage regulating circuit operating in quasi-resonant mode, turning ON a second switch of the second voltage regulating circuit after the first switch is turned ON for a half switching period, generating a current sensing signal by detecting a current flowing through the second switch, generating a peak signal, wherein the peak signal is adjusted when a voltage across the second switch is higher than a voltage reference at the time the second switch is turned ON, and turning OFF the second switch when the current sensing signal increases to the peak signal.

Growing community of inventors

Hangzhou, China

Guangzhuo Li