High-voltage wordline generator for low-power program operation in NAND flash memories

High-voltage wordline generation circuit with stage-controlled charge pump is developed for low-power NAND flash memories. The proposed stage-controlled charge pump controls an optimized number of stages according to the required program voltage. The proposed high-voltage generator provides sleep-mode operation by turning off the driving clock and regulators during the program verify operation. Using these techniques, the proposed high-voltage generator reduces about 50 percent of power consumption in comparison with a conventional scheme.