A 0.98ppm/°C, high PSR, low noise curvature-compensated CMOS bandgap reference with resistor-less low-pass filter

Abstract

In this paper, we proposed a 0.98-ppm/°C, high power supply rejection (PSR), low-noise and curvature-compensated bandgap reference with a resistor-less low-pass filter in 0.18-µm CMOS process. One prominent feature of the circuit is a low-temperature coefficient (TC) measuring less than 1-ppm/°C, achieved through the implementation of high-order curvature compensation. Another notable enhancement is the incorporation of a resistor-less low-pass filter, which effectively improves the PSR and noise performance at medium and high frequencies. Experimental results indicate that the circuit is able to realize an average output reference voltage of 1.21V@4V and an average low TC of 0.98-ppm/°C@-35°C-135°C at different corners. In addition, AC simulation results show that the circuit has a high PSR over the full frequency range and is capable of achieving PSR of -143.7dB@10Hz, -90.1dB@100KHz, and -134.0dB@100MHz. The output noise of the circuit measures 7.73nV/sqrtHz@10Hz, 30.60pV/sqrtHz@10KHz, and 11.75pV/sqrtHz@1MHz.