JPS6441576A - Clamping circuit - Google Patents

Clamping circuit

Info

Publication number
JPS6441576A
JPS6441576A JP62197742A JP19774287A JPS6441576A JP S6441576 A JPS6441576 A JP S6441576A JP 62197742 A JP62197742 A JP 62197742A JP 19774287 A JP19774287 A JP 19774287A JP S6441576 A JPS6441576 A JP S6441576A
Authority
JP
Japan
Prior art keywords
circuit
correction
level
sag
output
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP62197742A
Other languages
Japanese (ja)
Inventor
Yasushi Sano
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP62197742A priority Critical patent/JPS6441576A/en
Publication of JPS6441576A publication Critical patent/JPS6441576A/en
Pending legal-status Critical Current

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  • Picture Signal Circuits (AREA)

Abstract

PURPOSE:To prevent a sharp change accompanied with a correction from being given to a television signal by executing the correction of a sag as to a digital television signal obtained by an A-D conversion and executing the staged correction in one horizontal scanning period. CONSTITUTION:An analog television signal is A-D-converted by an A-D converting circuit 3, and a difference from a clamping level (reference level) is calculated by a first subtracter circuit 5. The difference between an output (c) of a register 6 which is a sag component and an output (f) of an integration circuit 10 is calculated by a second subtracter circuit 7 and sent to a comparator circuit 8. At the comparator circuit 8, when a correction remainder exists, a level generating circuit 9 is controlled in order to generate a level to correct further. In such a way, when a correcting value is gradually outputted and the correct correcting value s outputted by the integration circuit 10, the output of the second subtracter circuit 7 goes to zero, the level is not added to the integration circuit 10 thereafter, and the correction of the sag is completed.
JP62197742A 1987-08-07 1987-08-07 Clamping circuit Pending JPS6441576A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62197742A JPS6441576A (en) 1987-08-07 1987-08-07 Clamping circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62197742A JPS6441576A (en) 1987-08-07 1987-08-07 Clamping circuit

Publications (1)

Publication Number Publication Date
JPS6441576A true JPS6441576A (en) 1989-02-13

Family

ID=16379587

Family Applications (1)

Application Number Title Priority Date Filing Date
JP62197742A Pending JPS6441576A (en) 1987-08-07 1987-08-07 Clamping circuit

Country Status (1)

Country Link
JP (1) JPS6441576A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0651565A1 (en) * 1993-11-02 1995-05-03 Nec Corporation Circuit for compensating the drift of the level of the direct current of a video signal

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0651565A1 (en) * 1993-11-02 1995-05-03 Nec Corporation Circuit for compensating the drift of the level of the direct current of a video signal
US5508749A (en) * 1993-11-02 1996-04-16 Nec Corporation Sag compensation circuit for a video signal

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