A high efficiency regulated charge pump over wide input and load range

A multi-modes regulated charge pump with improved efficiency over wide input and load range is proposed in this paper. The output voltage is regulated to 5V when input is 4.5–2.7V. By alternating the switch network, it can realize 2x, 1.5x, and 1.33x conversion modes, which improves the efficiency over wide input range. During each mode, the output voltage is regulated by a controlled current source. The regulated charge pump is designed for a very wide load range (10mA to 500mA). A hybrid control scheme is proposed and analyzed to achieve a high efficiency over desired load range. Both of the simulation and test results are provided to verify the control scheme. The results show that the total loss at light load can be reduced by 56% to 83%.

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