A Low Power LDO Design for Battery-Less TPMS

Abstract

A low power LDO (Low Dropout Regulator) for power management of SoC applied in a battery-less TPMS (Tire Pressure Monitoring System) is presented and designed with automobile electronic 0.35μm CMOS technology. Based on simulation results, with typical 3.3V input and 3.0V output, presented LDO has a quiescent current of 63μA and delivers a current of about 30mA with a 99mV dropout voltage; the typical loop gain is up to 70.38dB which makes the output voltage 3V precise enough to the IP cores including CMOS temperature sensor, ADC, MCU and 433MHz data transmitter in the SoC and MEMS pressure sensor; and the typical PSRR is up to -67.36@8.263KHz. The low power LDO design is feasible for power management circuit of SoC in a battery-less TPMS.