基于皮尔斯振荡器的8MHz晶振电路设计

分析了石英晶体的等效模型和性能参数,设计了一款基于皮尔斯振荡器的8 MHz晶振电路,主要包括皮尔斯电路、使能控制及隔离电路、偏置电路和整形及电平移位电路.针对数字电路时钟为方波且数字电压域与模拟电压域不同的问题,设计了一个整形及电平移位电路,将晶体振荡器输出的正弦波整形成方波,且电路实现了双电压域工作.基于华宏0.11...

Design of 8 MHz Crystal Oscillator Circuit Based on Pierce Oscillator

The equivalent model and performance parameters of quartz crystal are analyzed,and an 8 MHz crystal oscillator circuit based on Pierce oscillator is designed.It mainly includes Pierce circuit,enable control and isolation circuit,bias circuit and shaping and level shift circuit.Aiming at the problem that the digital circuit clock is a square wave and the digital voltage domain is different from the analog voltage domain,a shaping and level shift circuit is designed to shape the sine wave output by the crystal oscillator into a square wave,and it can work in dual voltage domain.Based on HHGRACE 0.11μm 4P5M CMOS process,using Cadence Spectre to simulate the designed circuit,the results show that when the power supply voltage is 3.3 V,the output frequency of the crystal oscillator circuit is 8 MHz,the start-up time is 0.35 ms,and the output waveform accounts for 49.89%of the air and the operating current is 350μA.