一种超低功耗SAR A/D转换器

An Ultra-Low Power SAR A/D Converter

基于TSMC 0.18μm CMOS工艺,设计了一种用于植入式生物传感器的超低功耗逐次逼近型(SAR)A/D转换器。采用改进的单调开关切换方式,实现了超低功耗。采用动态比较器,消除了静态功耗。采用改进的自举开关结构,提高了采样开关在低电源电压下的线性度。后仿真结果表明,该SAR A/D转换器在1kS/s采样率、0.6V电源电压的条件下,整体功耗仅为8.7nW,有效位数达到9.76位。

An ultra-low power successive approximation register(SAR)analogue-to-digital converter for implantable biosensors was designed in TSMC 0.18μm CMOS process.An ultra-low power consumption was achieved by using a modied monotonic switching scheme.And a static power consumption was eliminated by using a dynamic comparator.A modified bootstrapped switch structure was adopted to improve the sampling switch linearity in low supply voltages.The post simulation results showed that the SAR A/D converter consumed 8.7 nW and achieved an ENOB of 9.76 bit at a sampling rate of 1 kS/s and a supply voltage of 0.6 V.