A low power CMOS current reference with process-insensitive temperature compensation

In order to reduce the influence of process on temperature coefficient of current reference, a CTAT voltage generation circuit is proposed in this paper, which can generate CTAT voltage with temperature coefficient insensitive to process. Combined with on-chip resistor which has process-independent temperature coefficient, a current reference with process compensation is designed. The proposed current reference is designed based on 0.18 μm CMOS technology with the power supply of 1.8 V, and the layout area is 100 μm*130 μm. Post-simulation results show that the current reference consumes 162nA and the output current is 32.5 nA at tt corner. Within the temperature range of -40~125℃, the temperature coefficients at tt, ff and ss corner are 39 ppm/℃, 45 ppm/℃ and 35 ppm/℃, respectively.