US Patent No. 10,772,170

TRIAC DIMMER DETECTION CIRCUIT, CHIP AND METHOD, AND LED DRIVING CHIP AND SYSTEM


Patent No. 10,772,170
Issue Date September 08, 2020
Title Triac Dimmer Detection Circuit, Chip And Method, And Led Driving Chip And System
Inventorship Weijia Yu, Shanghai (CN)
Minmin Fan, Shanghai (CN)
Assignee SHANGHAI BRIGHT POWER SEMICONDUCTOR CO., LTD., Shanghai (CN)

Claim of US Patent No. 10,772,170

1. A dimmer detection circuit comprising:a sampling unit, coupled to output of a rectifier and configured to output a signal representing a bus voltage;
a first comparator coupled to the sampling unit and configured to receive a first reference voltage and the signal, and generate a first processing signal;
a second comparator coupled to the sampling unit and configured to receive a second reference voltage and the signal, and generate a second processing signal; and
a control unit configured to receive the first processing signal and the second processing signal to detect the slope of the bus voltage change from the first reference voltage to the second reference voltage; wherein
the control unit outputs a dimmer detection result which indicates a leading edge phase cut or a trailing edge phase cut dimmer is present or neither by detects falling edge or rising edge of the first processing signal and the second processing signal.