积分型A-D变换器的积分误差及其最佳积分配置

Integral Error of an Integrating Type A-D Converter and Its Optimum Arrangement of Integration

本文从积分误差出发,提出一条用来衡量和估价积分型A-D变换器原理方案合理程度的直观判据,并在理论上确立变换器积分配置的最佳方式。揭示了目前流行的积分数字电压表在原理上的一个共同缺点,并指出今后发展高精度积分式数字电压表的新途径。

In an integrating type A-D converter, the relation between integral error and integral value of output voltage from the intergrator within one work period has been verified. This paper presents that 'the independence of the average output voltage from the integrator to the measured voltage and the approach of this average output voltage to zero level' can be used as an intuitive estimation of integral error of the converter, and it can be used as a criterion for assessing the principle scheme of the converter, in considering whether it is reasonable. The principle shortcomings of some common sorts of converters are pointed out.The (?)elation between the arrangement of integration and the integral error has been analysed. Theoretically, the optimum arrangement of integration is to arrange the integration in time sequence according to the symmetrical principle. This arrangement can reduce the integral error to a great extent, and it is a new approach for developing high accuracy integrating type digital voltmeter.