Ultra-low Power CMOS Multiple Voltage Reference with 3.9 ppm/°C Temperature Coefficient

A voltage reference with low temperature coefficient (TC), multipliable outputs and low power consumption is presented in this paper. The proposed reference circuit operating with all transistors biased in the subthreshold region, provides reference voltage of 342 mV. The outputs also can be multipliable to two or three, such as 684 and 1025 mV which is dependence on the requirement of system and the supply voltage. Subthreshold MOSFET design allows the circuit to work on a supply voltage as low as 0.8 V with an average current consumption of 6.4 nA at room temperature. The power supply rejection ratio (PSRR) with a 500f F capacitor load of 342 mV output voltage simulated at 100 Hz and 10 MHz is over than 51.9 dB and 42.2 dB, respectively. Monte Carlo simulation shows a mean TC is 3.9 ppm/degrees C over a set of 500 samples, in a temperature range from 30 degrees C to 100 degrees C. The layout area of the presented voltage reference is 0.0015 mm(2).