Signal processing

• US 20070090778A1
• Filed: 05/17/2004
• Published: 04/26/2007
• Est. Priority Date: 05/26/2003
• Status: Abandoned Application

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Wu, Chun, Goh, Hock
• Application Number:
  US10/557,342
• Publication Number:
  US 20070090778A1
• Time in Patent Office: Days
• US Class Current: 315/371
• CPC Class Codes: G09G 1/04 Deflection circuits ; Constructional details not otherwise provided for electron-optical arrangements H01J29/46, H01J37/04, H01J37/302
• CPC Class Codes: H04N 3/2335 with calculating means
• CPC Class Codes: H04N 3/32 Velocity varied in dependence upon picture information

Abstract

A signal processing circuit (1) comprises a first signal generator (10) which generates a DC-level (DL). A second signal generator (11) generates an AC-signal (AS) which is not related to the DC-level (DL). A combining circuit (12) combines the DC-level (DL) and the AC-signal (AS) into a combined signal (CS). And a common processing circuit (13) processes the combined signal (CS).

Claims

1. A signal processing circuit (1) comprising:

a first signal generator (10) for generating a DC-level (DL),

a second signal generator (11) for generating an AC-signal (AS) not being related to the DC-level (DL),

a combining circuit (12) for combining the DC-level (DL) and the AC-signal (AS) into a combined signal (CS), and

a common processing circuit (13) for processing the combined signal (CS).

2. A signal processing circuit (1) as claimed in claim 1, wherein the common processing circuit (13) comprises a preamplifier (130) for amplifying the combined signal (CS) to obtain an amplified combined signal (PCS), and wherein the signal generator (1) further comprises:

a low-pass filter (14) for separating the DC-level (DL) from the amplified combined signal (PCS) to obtain a separated DC-level (SDL),

a high-pass filter (15) for separating the AC-signal (AS) from the amplified combined signal (PCS) to obtain a separated AC-signal (SAS),

a first output amplifier (16) for amplifying the separated DC-level (SDL) to supply an output DC-level (ODL) to a first load (L1), and

a second output amplifier (17) for amplifying the separated AC-signal (SAS) to supply an output AC-signal (OAS) to a second load (L2).

3. A signal processing circuit (1) as claimed in claim 2, wherein the first load (L1) is a tilt coil, and wherein the second load (L2) is a scan velocity modulation coil.

4. A signal processing circuit (1) as claimed in claim 1, wherein the first signal generator (10) comprises an input for receiving an set signal (DCS) determining the DC-level (DL).

5. A signal processing circuit (1) as claimed in claim 3, wherein the second signal generator (11) comprises an input for receiving a video signal (VI) to supply the AC-signal (AS) being a derivative of the video signal (VI).

7. A display apparatus comprising a cathode ray tube (CRT), and a signal processing circuit (1) as claimed in claim 3, both the tilt coil (L1) and the scan velocity modulation coil (L2) being magnetically coupled with the cathode ray tube (CRT).

6. An integrated circuit (IC) comprising:

a first signal generator (10) for generating an DC-level (DL),

a second signal generator (11) for generating an AC-signal (AS) not being related to the DC-level (DL),

a combining circuit (12) for combining the DC-level (DL) and the AC-signal (AS) into a combined signal (CS), and

an output pin (P1) for supplying the combined signal (CS).