CMOS Charge Pump with Ultra-Low Current Mismatch

We propose an ultra-low current mismatch CMOS charge pump. With a cascode gain-boosting technique, the proposed charge pump obtains an ultra-high equivalent output resistance over a wide output-voltage range. A current mismatch between the discharging and charging current of less than 0.015 % has been simulated by using a 0.18-μm mixedsignal 1P6M 1.8-V CMOS process. The output current and the output voltage ranges of the proposed charge pump are 600 μA and 0.38−1.41 V, respectively.