连续式非线性A/D变换器的原理及其应用

The Principle and Application of Smooth Nonlinear A/D Converter

各种传感器,绝大多数的输出与输入呈非线性关系,因此,在应用中进行线性化处理至关重要。本文提出一种电路简单而效果却相当满意的称之为连续式非线性A/D变换器,它可以用于某些传感器进行线性化处理。它用于铂电阻数字测温,在-200℃到+650℃的整个温度范围内,绝对误差小于0.5℃,这是一般线性化电路很难达到的(或者能达到而电路过于复杂)。本文最后提出把连续式和折线式非线性A/D变换器结合起来,以进一步提高线性化精度,扩大应用范围。

There are various sensors, most of which have nonlinear outputralations. In application, it is very important to linearage them. This papersuggests a kind of circuit, named smooth nonlinear A/D converter, with thefeature of simplicity and effectivenss. It can be applied in some sensors withnonlinear characteristics. When using for the sensor of Pt resistance type, withthe range of --200℃ to + 650℃, the absolute error is less than 0. 5℃, which isnot so easy to realize in other of linearization. The paper also suggests thecombination of smooth type with piecewise linear nonlinear A/D converter inorder to improve the precision of linearization and enlarge the fields ofapplication.