布尔(Boolean)差分(BD)作为一种有力的故障分析方法,已被F.F.Sellers等人提出。V.Awar等人利用BD给出了一种实用的故障诊断方法,并把它用于译码电路。P.N.Marinos引入偏布尔差分的概念来作为从输入到输出的通道故障诊断,并借助于BD,把故障诊断扩展到内部故障和输入故障方面。关于故障诊断通道,采用Koga和Naemura提出的通道产生法(PGM),分析组合电路的结构,可得出最佳和最小的通道。但是,由于PGM仅以结构为基础进行电路分析,对具有多扇出的非树形组合电路,它并不保证通道的故障检测能力。本文研究了通过树形和非树形组合电路的通道的故障检测能力,并阐明了一种最佳最小的试验产生法。首先,我们选择一条从逻辑单元到输出端的通道。这一通道属于如下三种类型之一:(1)单通道(S-通道),通道中任何逻辑单元只有一个扇出;(2)多通道(M- Boolean Difference (BD) as a powerful failure analysis method has been proposed by F.F. Sellers et al. V.Awar and others use BD to give a practical fault diagnosis method and use it in decoding circuits. P.N.Marinos introduces the concept of a Boolean difference as a channel fault diagnosis from input to output and with the aid of a BD, extends fault diagnosis to internal faults and input faults. For fault diagnosis channels, the channel generation method (PGM) proposed by Koga and Naemura is used to analyze the structure of the combinational circuit to obtain the best and the smallest channels. However, since PGM performs circuit analysis based on the structure only, it does not guarantee the channel fault detection capability for non-tree combinational circuits with multi-fan-out. This article examines the ability of fault detection through the channels of tree and non-tree combinational circuits and illustrates an optimal and minimum test generation method. First, we choose a channel from the logic cell to the output. This channel belongs to one of three types: (1) single channel (S-channel) with only one fanout of any logical unit in the channel; (2) multi-channel (M-