Switching voltage regulator having a charge pump circuit

摘要

A voltage regulator (400) having a charge pump includes a bias current circuit (402) which produces a bias current (Ibias). The bias current (Ibias) is mirrored by a first mirror circuit (404) and multiplied by gain stage Q4beta and mirrored again by a factor "c" on the output of DMOS2. The same Ibias is mirrored by a ratio "b" and multiplied by the product of Q5beta and Q6beta. The push-pull current operation at the output terminal (416) is obtained by turning on and off switches SW1 (418) and SW2 (420) that are controlled by a clock signal. The voltage regulator (400) further includes an output voltage clamp (424) that keeps control of the Vboost voltage by controlling the amount of bias current (Ibias).