A Low-Power CMOS Voltage Reference with Current Loading Capability

Abstract

This paper presents a low power subthreshold CMOS voltage reference (CVR) with current loading capability. Based on the classical 2T CVR to achieve low temperature coefficient (TC), a sourcing PMOS is appropriately biased through a local negative feedback loop. Current loading capability is achieved without relying on an output buffer. The proposed CVR is designed in a standard 0.18-μm CMOS process. Simulation results show that the CVR is capable of delivering 300 μA while the generated Vref has less than 0.42% reduction. The minimum supply voltage is 0.5 V and typical power consumption is 3 nW. It achieves an average TC of 9 ppm/°C from -20 °C to 135 °C, line sensitivity of 0.069 %/v and power supply rejection of -65 dB@100Hz.