A CMOS supply-insensitive with 13ppm/°C temperature coefficient current reference

A simple all CMOS low temperature coefficient current reference is designed. Two opposite temperature coefficient supply-insensitive self-bias reference generators that have a function of threshold voltage, mobility and resistor are utilizing to compensate the first-order and second-order temperature curvature. The proposed circuit is designed in AMI 0.5μm process with 5V supply voltage over the temperature range of -45°C to 125 °C. The proposed circuit achieves a 16μA current with temperature coefficient of 13ppm/°C, the supply variation of the designed current is ±1.2% over ±10% VDD change and the accuracy over process variation is ±4.1%.