Ultralow-power temperature-insensitive current reference circuit

An ultralow power constant reference current circuit with low temperature dependence for micropower electronic applications is proposed in this paper. This circuit consists of a constant-current subcircuit and a bias-voltage subcircuits, and it compensates for the temperature characteristics of mobility thermal voltage VT, and threshold voltage V/sub TH/ in such a way that the reference current has small temperature dependence. A SPICE simulation demonstrated that reference current and total power dissipation is 97.7nA, 1.1/spl mu/ W, respectively, and the variation in the reference current can be kept very small within +4% in a temperature range from -20 to 100 /spl deg/C.