Traditional design o f low-dropout regulators offers the use of metal-insulator-metal (MIM) Mcompensation capacitors to prevent instability in the absence of load capacitor with equivalent series resistance (ESR). In addition to area efficiency achieved by replacing these capacitors with MOS transistors, the location of implant ed transfer function poles and zeros are adaptively changed according to the value of load current. The idea has been applied to stabilize a 1.2V, 100mA low-dropout regulator in a 0.18μm CMOS n-well process. Using the proposed technique, the regulator meets stability with a small 100pF MOS output capacitor and no ESR.

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