A fast transient-response LDO-CP with novel high voltage compensation structure in CMOS image sensors

This paper proposes a low-ripple and fast transient response low-dropout linear regulator-charge pump(LDO-CP) for CMOS image sensors(CIS). A novel high-voltage compensation structure is proposed, which accelerates the recovery of the output when the load is connected, and at the same time improves the influence of the discharge noise of the lower plate of the capacitor introduced by using the traditional compensator. In addition, a transient response enhancement circuit(TREC) is used to improve the transient response. Simulations were carried out in a 130 nm CMOS process. When the load capacitance is 8pF, the recovery time of the LDO-CP is 59ns, and the output ripple is $275 \mu \mathbf{V}_{p p}$.