Chengdu Monolithic Power Systems Co., Ltd.

Junxin Tan

Bo Yu

Shufa Jiang

Bairen Liu

Li Yang

Taofeng Li

A dimming circuit for dimming a current flowing through a light emitting device, having: a multi-function pin, configured to receive a dimming signal; wherein when the dimming signal is an analog voltage signal, an amplitude of the current flowing through the light emitting device is regulated based on the dimming signal; when the dimming signal is a pulse signal and a frequency of the dimming signal is in a first frequency range, a duty cycle of the current flowing through the light emitting device is regulated based on the dimming signal; and when the dimming signal is the pulse signal and the frequency of the dimming signal is in a second frequency range, the amplitude of the current flowing through the light emitting device is regulated based on the dimming signal.

Flexible dimming circuit and a method thereof

A short to ground protecting circuit for an LED driver for providing a power supply voltage for N LED strings. The LED driver has an output terminal for providing a power supply voltage for the N LED strings and N feedback terminals having N detecting voltages respectively. For each i from 1 to N, the iLED string is coupled between the output terminal and the ifeedback terminal, and the ifeedback terminal is configured to have the idetecting voltage. The short to ground protecting circuit receives a short threshold voltage and N open fault signals, and generates N short indicating signals. And on the premise of the iopen fault signal is valid, and if the idetecting voltage is less than the short threshold voltage for a preset time period, the ishort indicating signal is valid.

Short to ground and open protecting circuit, and associated protecting method

A short protecting circuit for a LED (Light-emitting Diode) driver for powering a plurality of LED strings, having: a short comparing circuit, configured to provide a plurality of short fault indicating signals; a first logic circuit, configured to provide a short fault signal based on the plurality of short fault indicating signals to indicate a short fault condition; a timing circuit, configured to provide a short protecting enable signal; and a second logic circuit, configured to provide a plurality of short isolating signals; wherein the short isolating signals are blocked when an open fault signal is valid.

Growing community of inventors

Hangzhou, China

Junxin Tan