A novel, low voltage, precision CMOS current reference with no external components

A novel, precision current reference with low temperature and supply sensitivity and without any external component has been designed in a 0.18mum CMOS mixed-mode process. The circuit is based on a bandgap reference (BGR) voltage and a CMOS circuit like a beta multiplier. The simulation results show max-to-min fluctuation of about 1% over a temperature range of -20degreesC to +100degreesC and supply voltage range of 1.1V to 2V with +/- 30% tolerance for all of the used on-chip resistors. The maximum nominal current variation in process corners is less than 3.5%.