一种面向Flash存算阵列的可调电荷泵

An Adjustable Charge Pump for Computing-in-Memory Array of Flash

Flash存算阵列在工作模式下需要用到不同内部驱动电压,因此基于当前各类Dickson型电荷泵,设计了一种针对Flash存算阵列的可调电荷泵。采用一种新型输出级的交叉耦合设计,解决了传统电荷泵最后一级阈值电压导致的低泵送效率的问题,并通过辅助MOS管增强了传统电荷泵中体源二极管对反向漏电流的抑制能力。55 nm CMOS工艺下的仿真结果表明,与改进前的电荷泵相比,在电源电压1.8 V和300μA的工作电流下,中间级反向漏电流减少了17.5%,输出级反向漏电流减少了73.1%。无反馈调节时,主电荷泵最高输出电压为9.56 V,电压效率达88.51%。PFM可调制模式下,可重构电荷泵能实现输出电压切换。

Due to the different internal driving voltages required by the computing-in-memory array of flash memory in the working mode,an adjustable charge pump for the array was designed based on various Dickson charge pump.A new cross-coupled design was adopted for the output stage to reduce the low pumping efficiency caused by the threshold voltage of the last stage in traditional charge pump.At the same time,the auxiliary MOS transistor was used to enhance the ability of the body-source diode in the traditional charge pump to suppress reverse leakage.The simulation results in a 55 nm CMOS process show that compared with the traditional charge pump,the reverse leakage of the intermediate stage is reduced by 17.5%,and the reverse leakage of the output stage is reduced by 73.1%under a power supply voltage of 1.8 V and a working current of 300μA.The maximum output voltage of the main charge pump is 9.56 V,and the voltage efficiency is 88.51%without feedback regulation.In the PFM adjustable mode,the reconfigurable charge pump can realize output voltage switching.