| 摘要 |
PURPOSE:To enable reproduction of waveform similar to the original one while to enable measurement of detailed waveform by performing two type of measurement having different phase split pitch then combining the measuring results of rough phase split with those of fine phase split to produce single measuring result. CONSTITUTION:Short period measurement for varying the phase as well as measurement of conventional period and executed to correct D.C. component of latter through the former. For example, the original waveform A in LSI to be measured with overall period of 400ns in conventional system is measured with 0.4ns step. Since 10mus is necessary for single phase step, the entire phase is scanned in 10ms to produce a differentiated waveform as shown on B because of passivation film. Consequently, when measuring with 16ns step over over the entire period of 400ns, it can be scanned in 250mus. When scanning with high rate, a waveform C scarcely different from the differentiated waveform is obtained. Where, it is corrected to coincide the waveform B with the waveform C to obtain finely splitted results.
|
