| 摘要 |
PURPOSE:To simplify the constitution by inputting an analog signal whose waveform is to be shaped to a circuit clamped to a threshold level of an FET and an FET circuit turned on and off by the same threshold voltage as the said FET so as to eliminate the need for an externally mounted waveform shaping circuit at the outside of an LSI circuit. CONSTITUTION:The zero cross waveform shaping circuit consists of the LSI circuit, which is provided with a timing generator TG generating Sin wave. An output from the TG is applied to a P MOSFETP1 via a point A' and clamped to a threshold value of the FETP1. Further, the Sin wave from the TG is applied to a point B', and a high and a low level of the threshold voltage is outputted by a P MOSFETP2. This output is applied to an inverter buffer comprising a P MOSFETP3 and an N MOSFETN1 and outputted after being waveform- shaped into a rectangular wave. Further, a waveform shaping circuit at the outside of the LSI circuit is eliminated and the circuit constitution is simplified. |
