Sensitive Voltage Readout ASIC For Micro Sensors

Due to their outstanding characteristics of low volume, light weight, multi functional, high reliablity and ease of integration with smart systems, Micro sensors based on Microelectronic and Micromachining technique are widely deployed in a variaty of areas, such as aerospace, military, process control and medical care. Among them, The largest volume applications to date are based on Micro accelerometers and Micro gyroscopes. As their name suggest, Micro accelerometer and Micro gyroscope are used for linear acceleration and angular acceleration measurements repectively, which are manufactured by MEMS process mainly adopted from traditional integrated circuit process. Since The minimum detectable signal are often determined by subsequent readout circuits in those sensors, high precison readout circuits tailored for those applications are highly desirable.A relatively sensitive readout ASIC suitable for most capacitive Micro inertial sensors is presented in this work. Firstly, a readout circuit diagram is proposed, then a single-ended operational amplifier, timing circuit and ESD protection circuit are designed in Chartered 0.35μm CMOS technology, these module's design work not only includes the circuit structure's design, the circuit schematic's Spectre simulation, the circuit component parameter values'calculation, but also includes the readout circuit layout's design, the layout's DRC, ERC, LVS physical verification, the layout's parasitic parameter extraction and the layout's post-simulation and so on, after the final layout is taped out, a testing PCB circuit is designed, then solder the packaged chip on the PCB , finally, utilize the testing instruments such as signal generator, oscillograph, electrometer to test the readout circuit chip's performance and have a good testing results.