Power Regulator, also called Voltage Regulator, is an on-chip device which provides the suitable power supply for the core from an external high voltage power supply. It is very convenient for an end user to supply the chip with only one voltage input although the entire chip needs two different voltages. Present design is a regulator that generates 1.8v voltage from 3.3v power supply. Based on SMIC 0.18um 3.3v process, each regulator unit will provide a maximum 60mA current. It can also provide up to 480mA current for the digital core via a proper combination of eight units.