| 摘要 |
<p>PROBLEM TO BE SOLVED: To highly accurately measure power supply noise information in a change time shorter than a CLK time interval which is generated in a semiconductor device; and suppress an increase of power consumption of a circuit required for the measurement, so as to facilitate circuit design.SOLUTION: In a circuit for measuring a power supply noise generated in a semiconductor device, observed analog power supply noise information 6 is compared with a reference voltage r1 by a comparison circuit 3; and a digital signal 7 as a comparison result is held by a holding circuit 4 that operates in asynchronization with a clock signal CLK. The holding circuit 4 that operates in asynchronization with the clock signal CLK holds digital signal information without deteriorating it even if the time interval of the clock signal CLK is long, for power supply noise information in a short change time which is generated between the time intervals of the clock signal.</p> |
