AK4707 Datasheet, PDF (22/42 Pages) Asahi Kasei Microsystems – AV SCART Switch

ASAHI KASEI
[AK4707]
„ Video Output Control (05H: D6-D0)
Each video output can be set to Hi-Z individually via control registers. These settings are ignored when the AUTO bit =
“1”.
TVV: TVVOUT output control
TVR: TVRCOUT output control
TVG: TVGOUT output control
TVB: TVBOUT output control
VCRV: VCRVOUT output control
TVFB: TVFB output control
0: Hi-Z. (default)
1: Active.
„ Clamp and DC-restore circuit control (06H: D6-D5, D3-D2)
Each CVBS and Y input has the sync tip clamp circuit. The sync tip voltage at each output is 0.7V (typ). This corresponds
0.35V (typ) at the SCART connector when matched by 75Ω resistors. The CLAMP1-0 bits select the input circuit for
ENCRC pin (Encoder Red/Chroma) and VCRRC pin (VCR Red/Chroma) respectively. VCLP1-0 bits select the source of
DC-restore circuit.
CLAMP1: Encoder Red/Chroma (ENCRC pin) input clamp control
0: DC restore clamp active (for RED signal. default)
1: Biased (for Chroma signal)
CLAMP0: VCR R/C (VCRRC pin) input clamp control
0: DC restore clamp active (for RED signal)
1: Biased (for Chroma signal. default)
VCLP1-0: DC restore source control
When the AUTO bit = “1”, the source is fixed to VCRVIN.
VCLP1 bit VCLP0 bit Sync Source of DC Restore
0
0
ENCV (default)
0
1
ENCY
1
0
VCRVIN
1
1
(Reserved)
Table 9. DC restore source control
MS0551-E-00
- 22 -
2006/10