电荷泵在低压电路中扮演着重要的角色.作为片上电荷泵,其面临的主要问题是:电压增益、电压纹波和面积效率.该文提出了一种新型的电荷泵电路,它采用辅助电荷泵、电平转移电路结构来产生不同摆幅的时钟,该时钟被用来驱动开关管的栅极,以有效控制开关管的电导,提高电压增益.由于采用PMOS管作为开关管,传输过程中避免了阈值电压损失.仿真结果显示,与以往文献中提到的电荷泵结构相比,该电荷泵具有更高的电压增益,开启时间短,纹波小,在低压应用环境优势更为突出.
Charge pump plays an important role in low supply voltage integrated circuits. Three important issues of on-chip charge pump circuits are voltage gain, output voltage ripple and area efficiency. A new charge pump is proposed in this paper which introduces a subsidiary charge pump and two voltage level shifters. The new structure can generate different magnitude clocks to drive the gates of switch transistors, which will improve voltage gain of charge pump greatly by means of effective control of conduction of them. At the other hand, we can avoid the threshold voltage loss by taking PMOS transistors as switch transistors. Simulation results show: The new charge pumps have higher voltage gain, shorter start up time and small voltage ripple compared with those proposed in earlier papers, especially in low supply voltage environment.