A 1.8–5.5-V LDO–BGR System With LACM Buffer for High PSRR in Camera Applications

This paper proposes a low-dropout regulator (LDO) and bandgap reference (BGR) system designed for camera applications, where high power supply rejection ratio (PSRR) and low output noise are critical. To achieve a stable output across a wide load range from no load to 600 mA a load-adaptive currentmirror (LACM) buffer is introduced. The LACM buffer effectively regulates current flow across different load conditions, minimizing power loss while ensuring stable operation. Additionally, a sampleand-hold (S/H)-based BGR is implemented to eliminate noise propagation from the supply voltage (VSYS) to the reference voltage (VREF), further enhancing PSRR. The proposed system was fabricated using a 0.18-μ m CMOS process