TH16509B - Clamp pulse circuit - Google Patents

Abstract

A clamp-on pulse generating circuit that includes Synchronized decision cycle for cutting Whether the external synchronization pulses are being imported or not. X Exclusive Or Circuit Switch Condition and pulse width sensing circuit for judging that Pulse-filled video signal Is the synchronization being imported? And a pulse generating circuit for generating a clamp-type pulse that Front edge or back edge of the external synchronous pulse The output from the synchronizer separator circuit and the output of the clamp pulse at the front edge. That is selected by the selection switch when pulses are synchronized. External forces were able to import and force to choose. And output of a clamp pulse on the back edge Of pulses synchronize Regardless of the presence of external synchronous pulses When the picture signal Packing with synchronous pulses is being imported.

Claims (3)

1.Clamp pulse generation circuit That includes: the endpoint, the input side, the synchronization. For importing external synchronous pulses; Decision Device, Synchronize For judging that such external synchronous pulses Is it being imported or not; Image input end for the import of image signals loaded with synchronized pulses; Image decision equipment for deciding whether such video signal Is it being imported or not; Pulse generating device for front edge clamp-on pulse generation Of pulses synchronize Such outside When the decision-making of the decision-making device, such synchronization Indicating that the pulse An external synchronization is being imported. And for generating a clamp pulse on the back edge of synchronizing pulses when the decision of the decision-making device such an image Indicates that the video signal is power Has been imported Regardless of the decision of the aforementioned synchronization equipment and; The clamp pulse output endpoint for the output of the clamp pulse at Generated by the device to generate such pulses to the outside 2. The clamping pulse generation circuit, corresponding to claim 1, with the decision device such image consists of an exclusive or With two input signals of pulses Synchronize such external And pulses synchronize within the said video signal. Switch Conditions for the selection of the output signal of such an exclusive circuit. When the decision of The aforementioned synchronization decision device indicates that such external synchronize pulses are being imported and the grounding level selection. When no external synchronous pulses are being imported and the pulse width detection circuit For comparison of pulse width Of side signal Out of the switch to change the said condition With a predetermined pulse width and the sensing output signal of the aforementioned pulse width sensing circuit, it is executed as a result of deciding that the signal is capable. Get imported or not 3. A clamp pulse generating circuit corresponding to claim 1 or 2, which is also included, is also included, the inward end of the control signal for the input of control signals from outside the control signal. When it is getting an input that causes the pulse generating device to generate clamped pulses at the front edge or the back edge of the synchronized pulse. In response to the control signal by Regardless of the decision-making of the aforementioned synchronization decision device.