Pulse And Oxygen Saturation Sensor Chip Research

With the rapid development and wide application of semiconductor technology and modern sensing technology,medical testing equipment is becoming more and more miniaturized,integrated and intelligent.Therefore,the use of semiconductor technology to study a pulse and oxygen saturation measurement of the chip is extremely important.The measurement circuit integrated on the chip can reduce the measurement system noise,power consumption and volume,to meet the requirements of portable medical equipment.Using UMC 0.18?m 1P6M CMOS process,a pulse and blood saturation sensor chip used to measure oxygen saturation and pulse is designed.The chip internal circuit includes two modules:pulse oximetry circuit and Pipeline ADC.At first,Lambert-Beer law is introduced,and the measuring principle of blood oxygen saturation is analyzed in detail.The theoretical model of the design chip circuit is obtained.Then the design of pulse oximeter circuit is analyzed,which mainly includes preamplifier circuit,suppressor base circuit,band-pass filter circuit and the second stage amplifier circuit.The performance indexes of each sub circuit are simulated in turn.The key circuit design of 12 bit Pipelined ADC is analyzed,which mainly include:sampling switch circuit,high speed comparator,voltage reference source,MDAC and digital calibration circuit.In the end,the simulation of pulse oximeter circuit and Pipeline ADC are also made,and the layout of the overall design and planning.With the operating voltage of 1.8 V,the gain of the whole system can reach 63 dB(6.5Hz-8.5 kHz).Equivalent input integral noise is 22.326V,and the power consumption of the whole system is less than 42.7mW.The noise of the measurement system can be effectively reduced,and out-of-band noise is reduced and inhibited.At the same time,the whole area of the measurement system can be reduced.As a result,the biomedical signal of narrow range can be processed.The simulation of Pipeline ADC is made.Under the 1Msps sampling rate,SNR is 68.2016dB,SNDR is 61.7818dB,and ENOB is 10.9bit.