A 42nA IQ, 1.5–6V VIN, Self-Regulated CMOS Voltage Reference With −93dB PSR at 10 Hz for Energy Harvesting Systems

This brief proposes a low-power voltage reference with low line sensitivity and high power supply rejection (PSR) under relatively wide supply voltage range. Excluding the small capacitors in start-up circuits, the proposed voltage reference is composed of only MOSFETs, most of which have been biased into the subthreshold region to achieve low power consumption. The self-regulating technique was also adopted to suppress the supply ripples and stabilize the supply voltage for the core reference circuits. The proposed reference circuit has been fabricated in 0.18- μm CMOS technology with a total chip area of 0.015 mm
²
. When supply voltage is 1.5 V, the measured reference voltage is 985 mV and the total quiescent current is 42 nA. The measured temperature coefficient (TC) from -40°C to 85°C is 60.86 ppm/°C, while the line sensitivity is as low as 0.003 %/V over 1.5 ~ 6V supply range. Besides, the measured PSR is -93 dB and -57 dB, at 10 Hz and 1 MHz, respectively.