调压型电荷泵

现今许多电子产品用电池作为电源，但是电池并不能稳定且持续保持固定的电压。为了提供系统稳定并且高于电源的电压，电荷泵与电压的调节是相当重要的。藉由带隙参考电压(bandgap reference)，调节电荷泵提供稳定的电压并不困难。但是在商业产品的制造上，带隙参考电压电路的制造却会增加生产上的复杂度。为了克服这个问题，本文将讨论如何不使用带隙参考电压而能调节输出电压的电荷泵。本设计的电荷泵使用交互连结式(cross-coupled type)的电路架构。并且利用一个弛张式震荡器来提供电荷泵驱动的频率。为了使用脉冲跨越模式(pulse-skip mode)来调节输出电压，利用修正弛张式震荡器内部的操作电流来控制频率。晶体管的门限电压(threshold voltage)被用来取代参考电压值，并且利用一个P型晶体管去检测输出电压的量值，若电压值高过设定的电压，则P型晶体管将导通，并且提供信号将弛张式震荡器关闭，此时电荷泵将停止升压。

Voltage Regulated Charge Pump

Nowadays, many electronic products are battery powered devices. However, most batteries are unable to maintain a steady voltage. In order to provide a steady voltage source, the charge pump and regulator are significant. With bandgap reference, to regulate the output voltage is easy. Nevertheless, the bandgap reference increases the manufacture complexity. In order to solve this problem, the charge pump regulated without bandgap reference is proposed in the thesis. The charge pump structure is cross-coupled type, and the clock is provided with a relaxation oscillator. In order to regulate the charge pump by pulse-skip mode, the current operated in the relaxation oscillator should be adjusted. The bandgap reference voltage was replaced by threshold voltage, and the output voltage is sensed with a PMOS transistor. If the output exceeds the default voltage, the PMOS transistor turns on, and the relaxation oscillator turns off. Meanwhile, the charge pump stops boosting.