A Frequency Detection Circuit for Constant ON-Time LED Driver Chip

Abstract

Abstract To meet the high-reliability requirements of switch mode power supply LED driver chips with constant on-time architecture, a detection mechanism circuit that can detect the switching frequency of the architecture is proposed. The detection circuit completes the conversion from switching frequency to output voltage through separate voltage tracing technology. The detection circuit uses the method of frequency error calculation to eliminate the interference of frequency jump on detection. The design is based on a 180 nm process simulation. The simulation results show that the detection mechanism has good linearity for frequency measurement and can eliminate the interference of frequency jump.