一种新型电流控制CMOS振荡器电路设计

Design of a novel current-controlled CMOS oscillator circuit

设计了一种基于华虹0.35 mm BCD工艺的新型电流控制CMOS振荡器电路,中心频率为1 MHz,宽温度范围内具有占空比高稳定性。不同于传统电流控制CMOS振荡器拓扑,结构简单,通过反相器阈值电压控制电流对电容的充放电状态切换,消除了延迟时间引起的上冲、下冲问题,具有良好的可移植性。Cadence Spectre仿真结果表明:-45～125℃范围内,振荡频率和占空比相对中心值的上下偏差分别为5.01%(-)到3.31%(+)、1.95%(-)到1.84%(+);方差分别为0.000 9、0.000 1。

A novel current-controlled CMOS oscillator circuit with 1 MHz frequency was designed based on 0.35 mm BCD process which realized high stability of frequency and duty cycle.The key aspect of the circuit with a simple structure and good portability,was the different topology with conventional CMOS oscillator,in which the capacitor charge state switching was controlled by the inverter threshold voltage,eliminating the overshoot and undershoot caused by delay.The results from the Cadence spectra simulation show that,with temperature range from-45 ℃ to 125 ℃,the proposed oscillator has a frequency deviation of 5.01%（-） to 3.31%（＋） and a duty cycle variation of 1.95%（-） to 1.84%（＋）,while variance are 0.0009 and 0.0001,respectively.