ADV7341BSTZ Analog Devices Inc, ADV7341BSTZ Datasheet - Page 61

• Manufacturer Part Number: ADV7341BSTZ
• Manufacturer: Analog Devices Inc

Specifications of ADV7341BSTZ

• Number Of Dac's: 6
• Adc/dac Resolution: 12b
• Screening Level: Industrial
• Package Type: LQFP
• Pin Count: 64
• Lead Free Status / RoHS Status: Compliant

The hue adjust value is calculated using the following equation:
where HCR
For example, to adjust the hue by +4°, write 0x97 to the hue
adjust control register.
where the sum is rounded to the nearest integer.
To adjust the hue by −4°, write 0x69 to the hue adjust control
register.
where the sum is rounded to the nearest integer.
SD BRIGHTNESS DETECT
Subaddress 0xBA
The ADV7340/ADV7341 allow monitoring of the brightness
level of the incoming video data. This feature is used to monitor
the average brightness of the incoming Y signal on a field-by-
field basis. The information is read from the I
this information, the color saturation, contrast, and brightness
controls can be adjusted (for example, to compensate for very
dark pictures).
The luma data is monitored in the active video area only. The
average brightness I
every VSYNC signal. The SD brightness detect register (Subad-
dress 0xBA) is a read-only register.
SD BRIGHTNESS CONTROL
Subaddress 0xA1, Bits[6:0]
When this feature is enabled, the SD brightness/WSS control
register (Subaddress 0xA1) is used to control brightness by
adding a programmable setup level onto the scaled Y data. This
feature can be enabled using Subaddress 0x87, Bit 3.
For NTSC with pedestal, the setup can vary from 0 IRE to 22.5 IRE.
For NTSC without pedestal and for PAL, the setup can vary
from −7.5 IRE to +15 IRE.
Hue Adjust (°) = 0.17578125° ( HCR
⎛
⎜
⎝
⎛
⎜
⎝
. 0
. 0
17578125
17578125
−
d
4
4
is the hue adjust control register (decimal).
⎞
⎟
⎠
⎞
⎟
⎠
2
+
+
C register is updated on the falling edge of
128
128
≈
≈
151
105
100 IRE
d
d
0 IRE
=
=
x 0
x 0
97
9 6
NTSC WITHOUT PEDESTAL
d
VALUE ADDED
− 128)
NO SETUP
2
C and, based on
Figure 68. Examples of Brightness Control Values
Rev. A | Page 61 of 108
POSITIVE SETUP
VALUE ADDED
The SD brightness control register is an 8-bit register. The seven
LSBs of this 8-bit register are used to control the brightness
level, which can be a positive or negative value.
For example, to add a +20 IRE brightness level to an NTSC
signal with pedestal, write 0x28 to Subaddress 0xA1.
To add a –7 IRE brightness level to a PAL signal, write 0x72 to
Subaddress 0xA1.
Table 51. Sample Brightness Control Values
Setup Level
(NTSC) with
Pedestal
22.5 IRE
15 IRE
7.5 IRE
0 IRE
1
SD INPUT STANDARD AUTODETECTION
Subaddress 0x87, Bit 5
The ADV7340/ADV7341 include an SD input standard
autodetect feature. This SD feature can be enabled by setting
Subaddress 0x87, Bits[5: 1].
When enabled, the ADV7340/ADV7341 can automatically
identify an NTSC or a PAL B/D/G/H/I input stream. The
ADV7340/ADV7341 automatically update the subcarrier
frequency registers with the appropriate value for the identified
standard. The ADV7340/ADV7341 are also configured to
correctly encode the identified standard.
The SD standard bits (Subaddress 0x80, Bits[1:0]) and the
subcarrier frequency registers are not updated to reflect the
identified standard. All registers retain their default or user-
defined values.
Values in the range of 0x3F to 0x44 may result in an invalid output signal.
0 × (SD Brightness Value) =
0 × ( IRE Value × 2.015631) =
0 × (20 × 2.015631) = 0 × (40.31262) ≈ 0x28
0 × ( SD Brightness Value ) =
0 × ( IRE Value × 2.075631) =
0 × (7 × 2.015631) = 0x(14.109417) ≈ 0001110b
0001110b into twos complement = 1110010b = 0x72
NEGATIVE SETUP
VALUE ADDED
Setup Level
(NTSC) Without
Pedestal
15 IRE
7.5 IRE
0 IRE
−7.5 IRE
+7.5 IRE
–7.5 IRE
ADV7340/ADV7341
Setup
Level
(PAL)
15 IRE
7.5 IRE
0 IRE
−7.5 IRE
1
Brightness
Control Value
0x1E
0x0F
0x00
0x71