A 900 mV 25 /spl mu/W high PSRR CMOS voltage reference dedicated to implantable micro-devices

In this paper, we describe an ultra low-voltage high PSRR bandgap voltage reference circuit dedicated to implantable biomedical applications. The circuit takes advantage of the low gate-source voltage of weak inversion CMOS transistor. And by using negative feedback to generate a regulated supply, the power supply rejection ratio (PSRR) of the proposed circuit can be increased up to 82 dB at 10 KHz. Although the circuit is designed for working under 900 mV supply voltage, the preliminary simulation result shows that it is able to work as low as 600 mV. The temperature coefficient is around 80 ppm//spl deg/C, while the circuit consumes 25 /spl mu/W of power.