本指南介绍了变容二极管小信号特性的几种测量方法。在本指南中，变容二极管定义为用作电压相关电容的双端装置。这种设备可以从直流频率使用到微波频率。示例包括从音频到微波频率的低噪声参数放大器、调谐元件、斩波器和移相器。提出了一种小信号等效电路，并对其有效性进行了讨论。概述了通过交流测量确定该电路元件的方法，并讨论了限制条件。半导体二极管IEEE 256的测试程序中讨论了直流测量技术的使用。 关于噪声测量的考虑，参见第9部分:线性双端口中的噪声，电子管测试方法-IEEE 158。

This guide describes several methods of measurement for the small signal characterization of varactors. For the purpose of this guide, a varactor is defined as a two terminal device used as a voltage-dependent capacitance. Such devices c a n be used from d c to microwave frequencies. Examples include low noise parametric amplifiers from audio to microwave frequencies, tuning elements, choppers, and phase shifters. A small-signal equivalent circuit is presented and its validity discussed. Methods for determining the elements of this circuit by means of ac measurements are described in general terms, and restrictions are discussed. The use of dc measurement techniques is discuss in Test Procedure for Semiconductor Diodes IEEE 256. For a consideration of noise measurements, see Part 9: Noise in Linear Two ports, Methods of Testing Electron Tubes - IEEE 158.