A Resistorless Voltage Reference Source for 90 nm CMOS Technology with Low Sensitivity to Process and Temperature Variations

A new compact low power voltage reference source for wireless and embedded applications is described. The reference voltage source has been designed in a mixed-signal UMC 90 nm CMOS process using subthreshold characteristics for generating a constant voltage of 423 mV at supply voltages from 1.1 V to 3.3 V with total current consumption 270 nA. The proposed circuit occupies 0.001 mm
²
chip area and achieves less than 110 ppm/degC for all process corners and temperature variation from -40degC to 125 degC. The power supply rejection ratio without any filtering capacitor at 100 Hz and 10 MHz is lower than -50 dB and -30 dB, respectively. The equivalent output voltage noise in the bandwidth from 1 Hz to 10 MHz reaches 218 muV
_RMS
.