Charge Pump Circuit Parallel Precharge Path

The patent applies preliminary action by precharging capacitors in parallel-connected stages before the charge pumping operation begins. The precharge circuit charges capacitors C1 and C2 (and additional capacitors in multi-stage configurations) to the power supply voltage VDD in advance, so that when pumping starts, the capacitors are already at optimal voltage levels. This eliminates the need for these capacitors to be charged during the pumping process, thereby improving current efficiency and reducing voltage drop even as the number of stages increases.

The patent applies segmentation by dividing the charge pump circuit into multiple parallel-connected stages, each with its own dedicated precharge path. Instead of having a single long precharge path that accumulates voltage drop, each stage has its own direct precharge connection to the power supply voltage VDD. This segmentation of the precharge function across parallel paths eliminates the cumulative voltage drop effect, allowing each capacitor to be precharged to full VDD level regardless of the total number of stages in the circuit.

The patent applies segmentation by separating the precharge function from the pumping function into distinct circuit paths. The precharge path uses dedicated precharge switches (e.g., switch 102) that connect capacitors directly to the power supply voltage VDD, while the pumping path uses separate pumping switches (e.g., switch 104) that transfer charge between capacitors. This functional segmentation allows each switch type to be optimized for its specific operation, improving current efficiency by eliminating the compounding effect of multiple switches in series during precharging, while maintaining manageable device complexity through modular parallel stage design.