Low-temperature-drift CMOS Voltage Reference Used in LED Driver

A low temperature drift CMOS voltage reference used in LED driver is designed.The principle of bandgap voltage reference is used in the proposed circuit.The structure is also improved to decrease the effect of offset voltage.Multi-output is also obtained to face the demand of LED driver chip.The proposed circuit is designed and simulated in CSMC 0.5 μm CMOS process.Three stable output voltage is get with 4 V VDD and they are 200 mV, 600 mV and 1 V.The temperature coefficient is 16.9 ppm/℃ when the temperature is changed between-45 ℃ and 85 ℃.The PSRR is greater than-70 dB at 1 kHz.