Based on the CSMC 0.5μm standard CMOS technology

designed a constant LED driver with disordered PWM control.The chip use disordered PWM technology to improve the LED refresh rate

use PWM synthesis technology to improve the LED grayscale

use constant current driving technology to reduce the LED light -declining.At 3V~5.5V supply voltage

-40℃~85℃

the circuit was simulated on Cadence spectre

the results show that following the input image data

LED refresh rate improved greatly;PWM synthesis model achieved 14 bits grayscale;dot correction mode achieved 6-bit chrominance correction;output current error accuracy is ±5%.