DC-DC变换器中一种高性能振荡电路的设计

采用 UMC 0.6μm BCD 工艺,设计了一种高性能双频振荡电路,并成功地将其应用于一款高效率、宽输入电压范围的 DC-DC 降压型开关变换器中。该电路作为整个芯片的核心模块之一,采用双电容充放电技术和 RS 触发机制,实现方波信号高、低电平时间精确可控。仿真结果表明,在考虑偏置电流、电源电压、温度以及 MOSFET 工艺波动的容差时,该振荡器的正常工作频率和占空比的最大偏差分别为7%和5%。

Design of a high performance oscillator circuit for DC-DC converter

A high performance,dual-frequency oscillator circuit based on UMC 0.6μm BCD process is designed for a high efficiency,wide input voltage range step-down DC-DC converter.As one of the core sub-blocks,the oscillator utilizes dual-ca- pacitor charging and discharging techniques and RS trigger to realize the cycle time of the square-wave being accurately adjustable .Simulation results show that the maximum deviation of frequency and duty cycle are respectively 7% and 5% under the tolerance of bias current,power voltage,temperature and MOSFET process.