A simple voltage reference source in weak inversion CMOS for ultra low-voltage and ultra low-power applications is presented. Its voltage reference is provided by the threshold voltage of an  n MOS transistor, as it can be verified in the theoretical deduction presented and by the BSIM3v3 simulations. The circuit simulated in a standard 0.35μm CMOS process provided a voltage reference of 512.03mV with a variation of just 33ppm°C for the temperature range of - 30°C to 100°C, and ± 0.42%/V variation for the power supply ranging from 750mV to 3.60V. The circuit takes a total area of 0.06mm 2  and requires only 800nA of biasing current.
['Luis H. C. Ferreira', 'Tales Cleber Pimenta', 'Robson L. Moreno', 'Wilhelmus Van Noije']
Ultra low-voltage ultra low-power CMOS threshold voltage reference