AD9880/PCB Analog Devices Inc, AD9880/PCB Datasheet - Page 38

• Manufacturer Part Number: AD9880/PCB
• Description: BOARD EVALUATION PCB AD9880
• Manufacturer: Analog Devices Inc

Specifications of AD9880/PCB

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

AD9880
0x04 7-3
INPUT GAIN
0x05
0x06
0x07
INPUT OFFSET
0x08
These bits provide a phase adjustment for the DLL to
generate the ADC clock. A 5-bit value that adjusts the
sampling phase in 32 steps across one pixel time. Each
step represents an 11.25° shift in sampling phase. The
power up default is 16.
7-0
These bits control the programmable gain amplifier
(PGA) of the red channel. The AD9880 can accom-
modate input signals with a full-scale range of
between 0.5 V and 1.0 V p-p. Setting the red gain to
255 corresponds to an input range of 1.0 V. A red gain
of 0 establishes an input range of 0.5 V. Note that
increasing red gain results in the picture having less
contrast (the input signal uses fewer of the available
converter codes). The power-up default is 0x80.
7-0
These bits control the PGA of the green channel. The
AD9880 can accommodate input signals with a full-
scale range of between 0.5 V and 1.0 V p-p. Setting the
green gain to 255 corresponds to an input range of 1.0
V. A green gain of 0 establishes an input range of 0.5 V.
Note that increasing green gain results in the picture
having less contrast (the input signal uses fewer of the
available converter codes). The power-up default is
0x80.
7-0
These bits control the PGA of the blue channel. The
AD9880 can accommodate input signals with a full-
scale range of between 0.5 V and 1.0 V p-p. Setting the
blue gain to 255 corresponds to an input range of
1.0 V. A blue gain of 0 establishes an input range of
0.5 V. Note that increasing blue gain results in the
picture having less contrast (the input signal uses
fewer of the available converter codes). The power-up
default is 0x80.
7-0
If clamp feedback is enabled, the 8-bit offset adjust
determines the clamp code. The 8-bit offset adjust is a
twos complement number consisting of 1 sign bit plus
7 bits (0x7F = +127, 0x00 = 0, 0xFF = −1, and 0x80 =
−128). For example, if the register is programmed to
130d, then the output code is equal to 130d at the end
of the clamp period. Note that incrementing the offset
register setting by 1 LSB adds 1 LSB of offset,
regardless of the clamp feedback setting.
The power-up default is 0.
Red Channel Gain
Green Channel Gain
Blue Channel Gain
Red Channel Offset Adjust
Phase Adjust
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0x09
0x0A
0x0B
0x0C
7-0
These eights bits are the red channel offset control.
The offset control shifts the analog input, resulting in
a change in brightness. Note that the function of the
offset register depends on whether clamp feedback is
enabled (Register 0x1C, Bit 7 = 1).
If clamp feedback is disabled, the offset register bits
control the absolute offset added to the channel. The
offset control provides a +127/−128 LSBs of adjust-
ment range, with one LSB of offset corresponding to
1 LSB of output code. If clamp feedback is enabled
these bits provide the relative offset (brightness) from
the offset adjust in the previous register. The power-up
default is 0x80.
7-0
If clamp feedback is enabled, the 8-bit offset adjust
determines the clamp code. The 8-bit offset adjust is a
twos complement number consisting of 1 sign bit plus
7 bits (0x7F = +127, 0x00 = 0, 0xFF = −1, and 0x80 =
−128). For example, if the register is programmed to
130d, then the output code is equal to 130d at the end
of the clamp period. Note that incrementing the offset
register setting by 1 LSB adds 1 LSB of offset, regard-
less of the clamp feedback setting. The power-up
default is 0.
7-0
These eight bits are the green channel offset control.
The offset control shifts the analog input, resulting in
a change in brightness. Note that the function of the
offset register depends on whether clamp feedback is
enabled (Register 0x1C, Bit 7 = 1).
If clamp feedback is disabled, the offset register bits
control the absolute offset added to the channel. The
offset control provides a +127/−128 LSBs of adjust-
ment range, with one LSB of offset corresponding to
1 LSB of output code. If clamp feedback is enabled
these bits provide the relative offset (brightness) from
the offset adjust in the previous register. The power-up
default is 0x80.
7-0
If clamp feedback is enabled, the 8-bit offset adjust
determines the clamp code. The 8-bit offset adjust is a
twos complement number consisting of 1 sign bit plus
7 bits (0x7F = +127, 0x00 = 0, 0xFF = −1, and 0x80 =
−128). For example, if the register is programmed to
130d, then the output code is equal to 130d at the end
of the clamp period. Note that incrementing the offset
register setting by 1 LSB adds 1 LSB of offset, regard-
less of the clamp feedback setting. The power-up
default is 0.
Green Channel Offset Adjust
Red Channel Offset
Green Channel Offset
Blue Channel Offset Adjust