| 摘要 |
PURPOSE:To measure a multipin integrated circuit by a method wherein a transmission gate is turned on and off by a mode changeover signal. CONSTITUTION:An information holding circuit is connected to an input terminal through a transmission gate T.G. The gate T.G that is controlled by a mode changeover signal is turned off in an ordinary operation and on in a test. When the gate T.G is off, the holding circuit is separated from an input circuit, and thus there is very little increase in the delay of operation speed caused by the holding circuit. Regardless of cutting a test signal by a switching relay, the holding circuit retains the value of the test signal for the first test cycle, which is thus effectively used as an input signal for the subsequent test cycle. |
