
ASAHI KASEI 
[AK4706] 
MS0507-E-00 
2006/05 
- 29 - 
3. Video Block 
 Video Switch Control 
The AK4706 has switches for TV, VCR and RF modulator. Each switches can be controlled via registers independently. 
When AUTO bit = “1” or STBY bit = “1”, these switch setting are ignored and set to fixed configuration (loop-through 
mode). Please refer the auto setup mode and standby mode.
    (04H: D2-D0)
VTV2-0 
bit 
TVVOUT pin 
Shutdown 
000 
(Hi-Z) 
ENCV pin 
(Encoder CVBS
or Y) 
ENCV pin 
(Encoder Y) 
ENCY pin 
(Encoder Y) 
VCRVIN pin 
(VCR CVBS 
or Y) 
TVVIN pin 
(TV CVBS) 
(reserved) 
110 
- 
(reserved) 
111 
- 
Mode 
Source of  
Source of  
TVRC pin 
(Hi-Z) 
ENCRC pin 
(Encoder Red,C
or Pb) 
ENCRC pin 
(Encoder C) 
ENCC pin 
(Encoder C) 
VCRRC pin 
(VCR Red,C 
or Pb) 
Source of  
TVG pin 
(Hi-Z) 
ENCG pin 
(Encoder Green 
or Y) 
Source of  
TVB pin 
(Hi-Z) 
ENCB pin 
(Encoder Blue 
or Pr) 
Encoder CVBS+RGB 
or Encoder YPbPr 
001 
Encoder Y/C 1 
010 
(Hi-Z) 
(Hi-Z) 
Encoder Y/C 2 
011 
(Hi-Z) 
(Hi-Z) 
VCR (default) 
100 
VCRG pin 
(VCR Green 
or Y) 
VCRB pin 
(VCR Blue 
or Pr) 
TV CVBS 
101 
(Hi-Z) 
(Hi-Z) 
(Hi-Z) 
- 
- 
- 
- 
- 
- 
 (Refer Note 23, Note 24)     
Table 14. TV video output 
          (04H: D5-D3)
Mode 
VVCR2-0 bit
Source of  
VCRVOUT pin
(Hi-Z) 
ENCV pin 
(Encoder CVBS
or Y) 
ENCY pin 
(Encoder CVBS
or Y) 
TVVIN pin 
(TV CVBS) 
VCRVIN pin 
(VCR CVBS) 
- 
- 
- 
Source of  
VCRC pin 
(Hi-Z) 
Shutdown 
000 
Encoder CVBS or Y/C 1 
001 
ENCRC pin 
(Encoder C) 
Encoder CVBS or Y/C 2 
010 
ENCC pin 
(Encoder C) 
TV CVBS (default) 
011 
(Hi-Z) 
VCR 
100 
VCRRC pin 
(VCR C) 
- 
- 
- 
 (Refer Note 23)                             
(reserved) 
(reserved) 
(reserved) 
101 
110 
111 
Table 15. VCR video output