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Blue Digital ALC Output LSBs

Green Digital ALC Output LSBs

Red Digital ALC Output LSBs

Automatic Level Control Enable

Digital ALC Output MSBs

TVP7002

SLES206 – MAY 2007

Subaddress

23h

Read only

7

6

5

4

3

2

1

0

Blue ALC Out [7:0]

Blue ALC Out [7:0]: Eight LSBs of 10-bit filtered digital ALC output for Blue channel. The corresponding two MSBs are located at

subaddress 27h. With the internal ALC loop enabled, the ADC dynamic range can be maximized by adjusting the coarse offset settings

based on the ALC read back values. See registers 1Eh–20h for analog coarse offset control. Twos-complement value.

ALC Out[9:0] = ADC output – 512

For bottom-level clamped inputs (YRGB):

•

Target ADC output blank level = 16 to avoid bottom level clipping at ADC

ALC Out[9:0] = 16 – 512 = –496 = 210h

•

Starting from positive offset, decrement YRGB coarse offset until ALC Out [9:0]

≤ –496

For mid-level clamped inputs (PbPr):

•

Target ADC output blank level = 512

ALC Out[9:0] = 512 – 512 = 0

•

Starting from positive offset, decrement PbPr coarse offset until ALC Out [9:0]

≤ 0.

Subaddress

24h

Read only

7

6

5

4

3

2

1

0

Green ALC Out [7:0]

Green ALC Out [7:0]: Eight LSBs of 10-bit filtered digital ALC output for Green channel. The corresponding two MSBs are located at

subaddress 27h. Twos-complement value. Also see register 23h.

Subaddress

25h

Read only

7

6

5

4

3

2

1

0

Red ALC Out [7:0]

Red ALC Out [7:0]: Eight LSBs of 10-bit filtered digital ALC output for Red channel. The corresponding two MSBs are located at subaddress

27h. Twos-complement value. Also see register 23h.

Subaddress

26h

Default (80h)

7

6

5

4

3

2

1

0

ALC enable

Reserved

ALC enable: Active high automatic level control (ALC) enable

0 = ALC disabled

1 = ALC enabled (default)

See the ALC Placement register located at subaddress 31h.

Subaddress

27h

Read only

7

6

5

4

3

2

1

0

Reserved

Red ALC Out [9:8]

Green ALC Out [9:8]

Blue ALC Out [9:8]

Red ALC Out [9:8]: Two MSBs of 10-bit filtered digital ALC output for Red channel. The corresponding eight LSBs are located at

subaddress 25h. Twos-complement value.

Green ALC Out [9:8]: Two MSBs of 10-bit filtered digital ALC output for Green channel. The corresponding eight LSBs are located at

subaddress 24h. Twos-complement value.

Blue ALC Out [9:8]: Two MSBs of 10-bit filtered digital ALC output for Blue channel. The corresponding eight LSBs are located at

subaddress 23h. Twos-complement value.

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