A low-voltage with high pumping efficiency charge pump for flash memory

Abstract

This paper proposed a high efficiency of power conversion and high pumping gain charge pump applied to the field of low power consumption like flash memory. The threshold voltage drop, body effect and the undesired charge transfer are three significant factors limiting the pumping gain and power conversion efficiency. In order to solve the threshold voltage drop and body effect, the charge transfer switches (CTS) are utilized in the proposed charge pump. What’s more, an optimized substrate control strategy and body-source diode are applied to eliminate undesired charge transfer for improving power efficiency. And a complementary branch scheme is employed to reduce the output voltage ripple. The proposed charge pump is implemented in SMIC 0.18 um standard technology and the simulation results indicate better performance and high efficiency of power conversion. The proposed charge pump satisfies the relevant specifications of the charge pump applied to flash memory.