| 摘要 |
A multi-mode charge pump drive circuit has a multi-mode charge pump, a switch control circuit, a current regulation circuit, an error amplifier, a variable resistance unit, and a mode selection circuit. The multi-mode charge pump is operated with a plurality of modes, each of which provides a different multiplicative ratio for converting an input voltage source into a drive voltage. The switch control circuit applies a switch control signal to the multi-mode charge pump. The switch control signal has a slew rate of edge for determining a transition span of the interchange between charging and discharging phases. The mode selection circuit controls the multi-mode charge pump to selectively operate with one of the plurality of modes. When the mode selection circuit changes the mode of the multi-mode charge pump, the mode selection circuit applies a mode change signal to the switch control circuit so as to reduce the slew rate of edge.
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