A CMOS temperature-independent current reference optimized for mixed-signal applications

A low-drift, high PSRR and high-accuracy CMOS temperature-independent current reference, optimized for mixed-signal applications is presented. The topology is based on bootstrap current references that present a PSRR up to 60 dB, which is required for the proposed applications since they employ circuits where high-frequency switching noise is present. The proposed approach was successfully verified in a standard CMOS 0.35 μm process. The electrical simulations and laboratory measurements confirm that for a power supply between 2.7 V and 3.6 V and temperatures between −40 °C to 80 °C range, the proposed current reference exhibits an accuracy of ±0.5% and a mean relative temperature dependency of 62.5 ppm/°C.