All CMOS temperature, supply voltage and process independent current reference

This paper describes an all CMOS current reference which generates temperature, supply voltage and process independent reference current. In such circuit, sub-threshold design and the body effect have been used to do the temperature compensation. Since only CMOS transistors are used here, the impact of process variation on reference current has been minimized. Cascode and feedback structure have been used to improve the power supply reject ratio. The Precision of reference current is ±5.2% when considering the process, supply voltage and temperature variation at the same time. The circuit has been designed and simulated with CSMC 0.5μm mixed-signal process.