摘要
研究一款适用于LED驱动芯片的CMOS振荡器电路.其工作原理是在环路振荡器中加入恒定电流源,以恒定电流对电容充电、MOS管对电容快速放电以产生锯齿波再经锁存器产生周期脉冲信号.与传统的环路振荡器相比,此电路的优点是振荡频率精确、波形稳定,振荡频率在一定的电源电压范围内对电源电压变化不敏感.此振荡器电路已经成功应用于一款LED驱动芯片中.
A CMOS oscillator used in monolithic LED driver is presented. The oscillator based on ring oscillator. The saw tooth waveform was formed by a capacitor charging with a designed constant current source and didchanging though a MOSFET. A periodic pulse was generated by passing the saw toochwave through a latch. Compared to the traditional ring oscillator, the frequency of this oscillator is stable, precise, power-supply-insensitive in a range of power supply. This oscillator had been used in a LED driver IC successfully.
出处
《电子器件》
CAS
2007年第3期890-893,共4页
Chinese Journal of Electron Devices
关键词
环路振荡器
周期脉冲信号
锯齿波
电源抑制比
ring oscillator
periodic pulse
saw tooth
power-supply rejection ratio
