| 摘要 |
PURPOSE:To enable a transistor (TR) having a smaller reverse base-emitter dielectric voltage by connecting 3rd and 4th TRs whose collectors are connected to a prescribed power supply between the base and emitter of 1st and 2nd TRs forming a two-way switch while each emitter and base are connected inbetween. CONSTITUTION:A clamp pulse synchronously with a pedestal period of a video signal is fed to an input terminal 2. While a TR Q5 is turned on by the clamp pulse, the base potential of TRs Q2, Q3 is lowered and when a voltage over the VBE is applied between the emitter and base, since the TRs Q6, Q7 are turned on, the voltage over the VBE is not applied between the emitter and base of the TRs Q2, Q3. Thus, it is not required to apply limitation to the component subject to DC recovery and a TR having a small base-emitter reverse dielectric strength is used to constitute the titled DC recovery circuit.
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