一种适用于DC/DC开关电源芯片的锯齿波振荡器设计

应用于手机等通信电子产品电源系统的DC/DC开关电源变换器芯片,要求具有高性能的锯齿波振荡器.鉴于此要求,设计了一款具有级冲放电电容的高性能锯齿波振荡器.基于华润上华CSMC 0.5 μmBiCMOS工艺库,利用Cadence Spectre软件进行电路仿真,在芯片系统典型应用环境下仿真得到锯齿波振荡频率为5 MHz,信号幅值为0～3 V.频率随电源电压在2.7～5.5 V变化范围和温度在-20～100 ℃变化范围而产生的偏移在±4%以内.该锯齿波振荡器的性能良好,已经成功应用于一款DC/DC降压开关电源芯片的设计之中.

Design of a Sawtooth-Wave Oscillator for DC/DC

DC/DC buck converter chip that used in the power system of correspondence electronic products such as mobile phone, requires to have the high performance sawtooth-wave oscillator .In view of this requirement, a Sawtooth-Wave Oscillator with two levels of charge -discharge capacitance was designed. Based on CSMC 0.5umBiCMOS technology , used the tool of Cadence Spectre to simulate. The simulation shows the saw-tooth wave oscillator has a 5MHz frequency and a 0V-3V peak-to-peak value under the typical application environment of the chip system. This sawtooth-wave oscillator has a high performance and has already used in the design of a DC/DC buck converter chip successfully.