Research Of Fast Start-up Of High Precision Measurement Circuit

This paper studies the fast start-up of high-precision measurement circuit. The temperature of the circuit varies severely in the duration of start-up, besides, the establishment of temperature balance takes much time, resulting in the severe variations of zero-bias and scale factor in the circuit, both of which need to be reduced by calibration. At the same time, both of them will drift gradually in process, which also needs to be reduced by calibration. With the help of high-temperature aging experiment, the stability of the circuit parameters can be improved, with the homogenization of temperature field, the time for temperature to get stable after the circuit starts can be shortened, what’s more, the stable temperature can be lowered.Firstly, the fast zero-bias calibration at the start-up moment is studied. In the duration of start-up, zero-bias varies severely and takes a long time to be stable, meanwhile, zero-bias will drift slowly as running. The temperature varies severely in the duration of start-up and takes a long time to be stable, the actual temperature cannot be obtained. This paper substitutes time for temperature. Zero-bias after the temperature is stable can be predicted accurately at the start-up moment with the method of piecewise modeling, resulting to the zero-bias calibration. After calibration, zero-bias can be stable quickly after the circuit boots, so that the repeatability of zero-bias is significantly improved.Secondly, the fast calibration of scale factor at the start-up moment is studied. The scale factor has severe variations and takes a long time to be stable, meanwhile, the scale factor has a slow drift as running. The temperature varies severely in the duration of start-up and also takes a long time to be stable, which makes the scale factor calibration impossible. Through the modification of the circuit, the calibration of scale factor becomes possible. With calibrated scale factor at the start-up moment, the circuit scale factor after the temperature is stable can be calibrated and the drift of scale factor can be modified. Thus, temperature influence on circuit scale factor is reduced and the repeatability of scale factor is improved. Thirdly, how high-temperature aging improves the stability of circuit parameters is studied. The effect of the ageing is analyzed, then the Arrhenius model is selected as high-temperature accelerated ageing model, next a high-temperature aging platform is established, finally, the effect of the high-temperature ageing is verified through experiments. After high-temperature ageing, the repeatability of zero-bias is significantly improved, and the circuit parameters get more stable.Fourthly, the effect of homogenization of temperature field on shortening the start-up time of the circuit is studied. The effect of homogenization of temperature field is analyzed, and the measures of homogenization of temperature field is illustrated which is verified through thermal simulation, finally, the design of homogenization of temperature field is proved correct by comparison experiments. After the design of homogenization of temperature field, the time for temperature to get stable after the circuit starts is further shortened, and the temperature after the circuit becomes stable is reduced.Finally, some shortcomings and expectations for further research were given.