CMOS current reference with supply and temperature compensation

The dependency of CMOS current reference on supply voltage and temperature is compensated by simply subtracting two current outputs with the same dependencies on the supply voltage and temperature. With this compensation scheme, a self-biased CMOS current reference has been implemented in a 0.25 m standard CMOS technology. The current reference provides 10.45 muA output current, while the supply and temperature dependencies are 1700 ppm/V and 720 ppm/degC, respectively. The current reference occupies only 0.002 mm active area and can operate down to 1.1 V.