Research And Design Of The Switch-Type Integrated Hall Sensor

With the rapid development of modern electronic technology, the sensor has alsobeen increasingly used by industrial automation, consumer electronics industry,homeland security, healthcare, and defense industry, etc. Now, the sensor with thefunction of information of detection and conversion has been an indispensable part ofthe field of electronic information technology. The Hall sensor with the function ofmagnetic field detection plays a vital role in the global sensor. The market for magneticfield sensors stood at$0.77billion in year2010and is expected to reach$1.4billion byyear2016at a compound annual growth rate of8.7%during the projected period.Meanwhile, the technology related the hall sensor continues to develop, the hall sensorwill have a better market prospects.Based on the process of HHNEC BCD350nm, the major work of the thesis is todesign a switch-type integrated Hall sensor. First, according to the understanding andanalysis of the principle, performance and design of the Hall sensing unit (Hall plate),the hall plate is achieved based on the corresponding process (HHNEC BCD350nm).Then, based on the performance and output parameters of the hall plate, the signalprocessing circuit is designed. In the design process, three problems focused on solvingare the readout and amplification of the weak hall signal, the cancellation of offsetvoltage of the hall plate, the compensation of the sensitivity temperature drift of hallplate. These analyzes provide experience and support of theory and technology for thesubsequent design.This article primarily includes the following four aspects:(1) According to the theory and technology related the Hall Effect, the Hall plate ofhigh sensitivity is achieved based on the process of HHNEC BCD350nm.(2) Though the combination of switched capacitor and amplifier, the circuitachieves the function of readout and amplification of the weak hall signal.(3) Though the quadrature current method and the sample-and-hold circuit,switched capacitor, the circuit eliminates offset voltage of the hall plate and inhibitsoffset voltage of the ops. (4) Though the temperature compensation technology, the circuit can balance thesensitivity temperature drift of hall plate, which optimizes the temperature performanceof the chip.In the process of chip design, the circuit is designed though Cadence’s schematicedit tool, and is simulated and verified though the Cadence’s specture. It’s layout isdesigned though Cadence’s Virtuoso layout edit tool, and layout and circuit has beenverified by DRC, LVS, XRC, etc.