| 摘要 |
PURPOSE:To detect a clip by a simple circuit with precision by comparing a difference in potential across the conductive channel of an amplifying element with a fixed value. CONSTITUTION:Transistor TRQ1, an amplifying element, is provided with switching TRQ2 and diode D1 as a comparing method and further provided with voltage source E as a reference voltage for a comparison. Here, voltage E across reference voltage source E is selected as shown by the equation. Here, VCE(SAT) is a voltage by which VCE of TRQ1 gets saturated, VD the forward voltage of diode D1, and VBE the base-emitter voltage of TRQ2. Therefore, when an input signal is small, diode D1 is in a reverse bias state and TRQ2 is OFF, but TRQ1 is getting saturated, diode D1 is biased forward, allowing a current through TRQ2. As a result, the saturation operation of TRQ1 can be detected. |
