A 65nm CMOS low-power, low-voltage bandgap reference with using self-biased composite cascode opamp

In this paper, we present a low-voltage low-power CMOS bandgap voltage reference (BVR) based on the self-cascode self-biased op-amp. The current mirror mismatch error resulting from the channel length modulation (CLM) effect has also been compensated by using composite transistors. This proposed circuit, implemented in 65nm IBM CMOS process, which generates a reference of 364mV from a power supply of the 1.2V and consumed the 28 μW at room temperature. The power supply rejection ratio is greater than 60 dB for frequency below 10 kHz. The proposed bandgap achieves a temperature coefficient(TC) of 4.7ppm/°C without trimming for the temperature range(TR) from 0°C to 100°C and the 0.75mV/V of ±10% supply voltage variations.