Abstract: This simple charge-pump voltage inverter produces more than -10V at no load, and more than 200mA while the output voltage remains greater than the input. The versatile switched-capacitor charge pump is easy to use and requires no inductor. It can double a positive voltage or convert a positive voltage to negative. For some applications in which only a positive supply is available, the system must generate a negative voltage of larger magnitude than the positive rail. For that purpose, the circuit of Figure 1 inverts the input voltage and doubles the resulting negative output at the same time. The voltage inverter shown (IC1) converts a positive input to a negative output voltage, normally with an absolute magnitude lower than that of the input. But in this circuit, the two Schottky diodes and the two capacitors at the output produce a higher output voltage. Figure 1. This simple circuit derives -10V from +5V. The expected output is VOUT = -(2xVIN - 2VD- IOUT* RO), where VD is the voltage drop across a diode, IOUT is the output current, and RO is the output resistance. While the maximum expected voltage is -10V, overshoot across the capacitors due to parasitic inductance in the capacitors and traces produces more than -11V at no load (Figure 2). Figure 2. The circuit in Figure 1 above produces more than -10V at no load, and more than 200mA while the output voltage remains greater than the input. This design idea appeared in the May 26, 2005 issue of EDN magazine. 相关型号   APP 3659: Dec 14, 2005 MAX889 高频、稳压型、200mA、反相电荷泵 完整的数据资料 (PDF, 312kB) 免费样品 自动更新 需要自动接收最新发布的应用笔记吗？请订阅EE-Mail™ (English only)。 我们期待您的反馈！ 喜欢？不喜欢？有待改善？或为我们提供建议？请与我们联系 — 我们将根据您的意见或建议改善我们的工作。 网页评价或提供建议   下载，PDF格式 (34kB)  AN3659, AN 3659, APP3659, Appnote3659, Appnote 3659