Title:
SWITCHING CIRCUIT FOR VIDEO SIGNAL
Document Type and Number:
Japanese Patent JPS6211375
Kind Code:
A
Abstract:
PURPOSE:To simplify a titled circuit and to reduce cost by accomplishing switching of two input video signals by means of two emitter follower circuits and one switch. CONSTITUTION:A first input video signal 1 is supplied to the first emitter follower circuit 101 by means of AC coupling, and is made an output video signal t through the circuit 101. And the second input video signal 3 is supplied to the second emitter follower circuit 102 likewise, and is also made the output video signal through the circuit 102. The vias voltage 4 determined by resistors 17 and 18 are set at a value higher than voltage 2 determined by resistors 12 and 13, to cut off the transistor TR 19 of the circuit 102 when the switch 20 is turned off. But when the switch 20 is turned on, the transistor TR 14 of the circuit 101 is cut off. So, only either one of the signal 1 or 3 is outputted as the signal 5 in accordance with the on/off operation of the switch 20. The switching circuit thus is simplified.
Inventors:
YABIKU HIDEO
Application Number:
JP15070685A
Publication Date:
January 20, 1987
Filing Date:
July 09, 1985
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
H04N5/268; H04N5/44; (IPC1-7): H04N5/268; H04N5/44
Domestic Patent References:
| JPS568339B2 | 1981-02-23 |
Attorney, Agent or Firm:
Akira Kobiji (2 outside)
Previous Patent: Electric wave selection structure and an electric wave selection method
Next Patent: JPS6211376
Next Patent: JPS6211376