一种基于石墨烯霍尔器件的读出电路设计

A Readout Circuit for Graphene Hall Element

摘要: 为了实现对石墨烯霍尔器件的高精度检测，采用前端放大以及模数转换器技术，设计了一款模拟前端读出电路.该读出电路包括前端放大器、低压差线性稳压器件、施密特触发器以及10 bit/1 MHz逐次逼近模数转换器四大部分.读出电路芯片采用SMIC 0.18μm 1P6M 标准CMOS工艺实现.后仿真结果显示，在电源电压3.3 V，输入信号50 kHz和1 M Hz时钟频率下，无杂散动态范围（SFDR）为71.294 dB，信噪失真比（SNDR）达到59.538 dB，有效精度（ENOB）达到9.59 bit，可检测0.00013T特斯拉的磁场变化，满足石墨烯霍尔器件的检测要求.

Abstract: In order to realize the high resolution detection of grapheme hall element,amplifier and analog-to-digital technique is adopted to design a analog front-end readout circuit.The circuit consists of amplifier,low dropout regulator (LDO),Schmitt trigger and 10 bit/1 MHz Successive Approximation Analog-to-Digital Converter (SAR ADC).The readout is implemented in SMIC 0.18 μm 1P6M CMOS process.The post-simulation results show that in 3.3 V power supply,50 kHz input frequency and 1 M Hz clock frequency,the SFDR is 71.294 dB,SNDR is 59.538 dB,ENOB is 9.59 bit,detection accuracy is 0.00013 T,meets the detection requirement of grapheme hall element.