A 0.23 μw 6.46 ppm/°C Resistor Less Bandgap Voltage Reference with High PSRR and Wide Range of Power Supply for Biomedical Applications

This paper presents a resistor-less bandgap reference (BGR) with low temperature coefficient (TC), low power consumption and high power supply rejection ratio (PSRR). The circuit is composed of a pre-regulation circuit, a start-up circuit, a bias circuit, a complementary-to-absolute-temperature (CTAT) voltage generator, a proportional-to-absolute-temperature (PTAT) voltage generator, and a filtering circuit. This paper proposed 'a dual power supply rejection ratio improvement technology' by using a pre-regulator (PR) circuit and a two-stage filtering (TSF) circuit to solve the problem of low power supply rejection ratio (PSRR) of the traditional low power bandgap reference, and greatly broadens the range of the supply voltage, so that the proposed BGR can well meet the requirements of accuracy and power consumption for biomedical devices. Designed in 55 nm standard CMOS, the proposed BGR achieves a simulated TC of 6.46 ppm/°C at 1.6 V supply within -20°C to 100°C and a power consumption of 0.23 μ W. The line regulation is 0.011% / V from 1.2 V to 3.3 V. Its is 136 μ s.