A temperature-compensated current source with high output impedance

In this paper we describe the design and simulations of an accurate low compliance voltage current source with high output impedance in 1.8-V, 0.18μm CMOS technology, which compensated from temperature variations. Using a second-order temperature compensated current reference caused to obtain approximately temperature-independent current source. Also in this design we achieved high output impedance by using a negative feedback, without increasing Compliance voltage. The simulation results show that compliance voltage is 165-mV at 50μA and its temperature coefficient is 87 ppm/°C in temperature range from 0°C to 120°C. It is important to noted, three main specifications of current sources, temperature independence, high output impedance and low compliance voltage are achieved in proposed circuit. The total consumption power is 206 μW at 1.8 supply voltage.