| 摘要 |
PURPOSE:To simplify measurement with reliability improved, by separating a power supply at the negative side of a dynamic FF from that at the negative side of a static FF. CONSTITUTION:Power supply Vss1(-) for dynamic FFs 103 to 105 is separated from power supply Vss2(-) for static FFs 107 and 108. During measurement, the potential of Vss1(-) is regarded as that at the signal input terminal, and an input signal is supplied from input terminal 101, thereby setting the state of static FFs following FF107. At this time, Vss1(-) is supplied as an input signal at the same potential as Vss2(-1), and at the point in time when output Q of FF105 is established with its potential nearly equal to that of positive-side power supply VDD(+), Vss1(-) is supplied at the same potential as VDD(+). As a result, FFs 103 to 105 do not operate, so that this circuit will be fixed to the state of circuits following FF107. Consequently, electric characteristics such as the leak current and output current of the circuit formed of static FFs can be measured under no influence of dynamic FFs. |
