A Novel 0.8-V 79-nW CMOS-Only Voltage Reference With-55-dB PSRR @ 100 Hz

A novel 79-nW CMOS-only subthreshold voltage reference with 328-mV output voltage, which works down to 0.8-V supply voltage, is presented in this brief. In order to reduce the area and power consumption, the proposed circuit avoids the use of resistors and bipolar transistors. A current subtracting technique is proposed to realize the temperature compensation of reference current. Instead of the op-amp in traditional circuits, some cascode current mirrors are used to enhance the power supply rejection ratio (PSRR). A novel structure consisting of a 1.8-V MOS transistor and a 3.3-V MOS transistor is utilized to accomplish the voltage temperature compensation and to further reduce the power consumption of VREF generator. The proposed voltage reference was fabricated in 0.18-mu m CMOS process. The measured results show that the temperature coefficient of the output voltage is 33.8 ppm/degrees C in the range from 10 degrees C to 100 degrees C, the PSRR is -55 dB @ 100 Hz at 1.2-V power supply, and the line regulation is 0.21%/V in a supply voltage range of 0.8 to 3.4 V. What is more, the power dissipation is 79 nW, and the chip area is 0.01 mm(2). It is suitable for low-power applications.