一种高精度张弛振荡器的设计

摘要

A relaxation oscillator with high temperature rejection characteristics is presented. This relaxation oscillator adopts the temperature compensation method of single chip relaxation oscillator,using well diffuse resistor with positive temperature coefficient to compensate. Fabricated in a 0. 35 μm CMOS process and verified by the Cadence simulation,this relaxation oscillator has only the temperature coefficient of 404í10-9/℃ in the range of-45 ℃ ~55 ℃. Also, the oscillation frequency has slim influence of the temperature change. This circuit has applied successfully in industrial control chip.%提出一种新的带温度补偿的张弛振荡器，采用正温度系数的阱电阻实现输出频率在大范围温度变化下保持稳定。该电路采用0.35μm的CMOS工艺实现，利用Cadence进行仿真验证。仿真结果显示，在-45℃~55℃范围内，该张弛振荡器的温度系数仅为404×10-9/℃。该振荡器振荡频率受温度影响很小，已经应用于工业控制类芯片中。