A Wideband High PSRR LDO Used in RF Transceivers

Based on the 55nm CMOS process, an LDO circuit with high PSRR in all frequency bands is designed to power the RF transceiver. An Active Low-Pass Filter (ALPF) is used to reduce the influence of the reference voltage on the PSRR of the LDO and improve the PSRR of the LDO in the mid-band band. Considering the problem of slow power-on charging of a large capacitor in the active low-pass filter, a Charging Circuit (CC) is designed to reduce the power-up time of the circuit. A compensation circuit is added to reduce the effect of the zero point on the circuit caused by the ESR resistance on the off-chip capacitor; The circuit is powered by 2.0V voltage, under the load of 60mA, the PSRR is less than −44dB in the band of from 1Hz to 1 GHz, the power-on time of the supply is $10\mu \mathrm{s}$, the power-on time of the LDO is $72\mu s$, and the static power consumption of the whole LDO is 270µA. Besides, the LDO has good transient response characteristics.