This paper proposes an adaptive wireless power management IC for implantable sensor systems like smart IOL (Intraocular Lens). Depending on the phase, the system operates the sub-circuits with adaptive on/off for low power operation and reducing the noise effect of the inductive link. The adaptive PMIC selectively turns the circuit on/off, which reduces the load power, thereby generating a high DC voltage with a low ac voltage. If power is charged enough, the wireless power transfer (WPT) is cut off and the circuit is driven by internal power. A supply-change circuit and a phase detector automatically change the power supply and phase, respectively. The proposed wireless system can be used for noise-sensitive implantable sensor systems and is built with 180 nm standard process that supports 1.8V/5V transistors. The wireless system operates at a carrier frequency of 13.56MHz.