关键词: A/D转换器, 逐次逼近型ADC, 阻容混合型DAC, 温度码

Abstract: A 10 bit successive approximation analog-to-digital converter(SAR ADC)based on a 0.18μm CMOSprocessispresented.Theproposed SARADCemploysa RC-capabledigital-to-analog converter(DAC)to achievethetrade-off between areaand performance,and the high bitsof the DACemploy temperaturecodes to improvethelinearity of the DAC.A static comparator structurewith small offset voltageisused in the ADC,and ahigh-gain pre-amplifier isadded between the DACand thecomparator to eliminate the effectscaused by comparator offset voltage on the ADC performance.The simulation results show that the effective number of bits(ENOB)of the ADCis9.99 bitsand the signal-to-noise ratio(SNDR)is61.9 dB when the power supply voltageis2.8 V,thesampling rateis116 kS/s,theinputsignal frequency isabout57 kHz,and theswing is0.8 V.Spurious-freedynamic range(SFDR)is75.57 dB,thetotal power consumption isapproximately 1 mW,and the areais0.069mm².

Key words: A/Dconverter, SARADC, RC-capable DAC, temperaturecode