基于 0.18 μm CMOS工艺设计了一款低温漂延时电路,适用于不能使用锁相环电路又对信号传输精度有要求的低功耗传感检测应用.采用正温度系数的偏置电压,通过电流镜为延时电路提供一个正温度系数的偏置电流,利用偏置电流约束电路的延时温漂,实现温漂粗调.采用数字时间转换器,通过外部输入配置,对粗调后的延时进行动态细调,使得延时电路具有更高的动态稳定性和更低的温漂特性.电路测试结果表明,在 3.3V的电源电压下,-55~125℃内延时电路的温度系数为 125×10-6/℃,静态功耗仅为 0.72 mW.
Based on 0.18 μm CMOS process,a low-temperature drift delay circuit was designed,which was suitable for low-power sensing detection applications that phase locking loop circuits could not be used but the circuits were required to transmit high precision signals.A bias voltage with positive tem-perature coefficient was used to provide a bias current with positive temperature coefficient for the delay circuit through the current mirror.And the bias current was used to constrain the delay temperature drift of the circuit to realize the coarse adjustment of temperature drift.By using digital time converter,the delay after coarse adjustment was dynamically fine adjustment through external input configuration,so that the delay circuit had higher dynamic stability and lower temperature drift characteristics.The measurement results of the circuit show that the temperature coefficient of the delay circuit is 125×10-6/℃ at-55-125℃,and the static power consumption is only 0.72 mW under the supply voltage of 3.3 V.