A Novel Current Mismatch Compensation Technique for Use in Charge-Pump

In this paper a charge-pump with a mismatch compensation technique is presented that generates up and down currents with very low gain mismatch in a wide voltage range of control voltage. The proposed charge-pump is designed in TSMC 0.18-μm standard technology. The compensation circuit is added to a conventional drain-switching charge-pump. The design implementation is done in cadence-virtuoso CAD tool. Simulation results of the proposed charge-pump are done with Spectre simulator and reveals that the current mismatch is removed perfectly in the wide range of control voltage and also the linearity range is enhanced from single point to 0.1~1.7 V of supply voltage (1.8V) when compared with the conventional charge-pump without compensation technique.

Keywords:

mismatch compensation technique , linearity , charge-pump , frequency synthesizer , CP-PLL