| abstract |
An input waveform signal is converted into a digital peak value signal by an A/D converter, and the digital peak value signal is input to one input terminal A of a comparator. The other input terminal B of the comparator receives a preset digital peak value signal from a memory. These input signals are compared by the comparator. The content of the memory is reduced at a predetermined rate. If the comparator detects that the currently input waveform level is larger than the continuously reduced level of the memory, i.e., if A>B, a new waveform level is loaded in the memory. As a result, the output from the comparator is inverted. That is, condition A>B is changed into condition A<B. The timing of this change in condition serves as a peak timing of the input waveform signal. |