ADV7301AKST Analog Devices Inc, ADV7301AKST Datasheet - Page 45

• Manufacturer Part Number: ADV7301AKST
• Description: IC DAC VIDEO HDTV 6-12BIT 64LQFP
• Manufacturer: Analog Devices Inc
• Type: Video Encoderr

Specifications of ADV7301AKST

• Rohs Status: RoHS non-compliant
• Applications: DVD, Set-Top Boxes
• Voltage - Supply, Analog: 2.37 V ~ 2.63 V
• Voltage - Supply, Digital: 2.37 V ~ 3.6 V
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Number Of Dac's: 6
• Adc/dac Resolution: 12b
• Screening Level: Commercial
• Package Type: LQFP
• Pin Count: 64
• Lead Free Status / RoHS Status: Compliant

HD SHARPNESS FILTER CONTROL AND ADAPTIVE
FILTER CONTROL
[Subaddresses 20h and 38h-3Dh]
There are three filter modes available on the ADV7300A/
ADV7301A: Sharpness Filter Mode and two adaptive filter
modes.
HD Sharpness Filter Mode
To enhance or attenuate the Y signal in the frequency ranges
shown in Figure 63, the following register settings must be used:
HD Sharpness Filter must be enabled and HD Adaptive Filter
Enable must be set to disabled.
REV. A
INPUT SIGNAL:
Figure 62. Signal Input (Ramp) and Selectable
Gamma Output
STEP
300
250
200
150
100
50
0
0
SIGNAL INPUT
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
50
FILTER A RESPONSE – Gain Ka
100
FREQUENCY – MHz
LOCATION
1.5
0.3
1.8
0.5
Figure 63. Sharpness and Adaptive Filter Control Block
150
200
250
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
–45–
FILTER B RESPONSE – Gain Kb
To select one of the 256 individual responses, the correspond-
ing gain values for each filter, which range from –8 to +7, must
be programmed into the HD Sharpness Filter Gain Register at
Address 20h.
HD Adaptive Filter Mode
The HD Adaptive Filter Threshold A, B, C Registers, the HD
Adaptive Filter Gain 1, 2, and 3 Registers, and the HD Sharp-
ness Filter Gain Register are used in Adaptive Filter Mode. To
activate the adaptive filter control, the HD Sharpness Filter and
HD Adaptive Filter Enable must be enabled.
The derivative of the incoming signal is compared to the three
programmable threshold values: HD Adaptive Filter Threshold
A, B, C. The recommended threshold range is from 16–235,
although any value in the range of 0–255 can be used.
The edges can then be attenuated with the settings in HD
Adaptive Filter Gain 1, 2, 3 Registers and HD Sharpness Filter
Gain Register.
According to the settings of the HD Adaptive Filter Mode con-
trol, there are two adaptive filter modes available:
1. Mode A is used when Adaptive Filter Mode is set to “0.” In
2. Mode B is used when Adaptive Filter Mode is set to “1.” In
FREQUENCY – MHz
this case, Filter B (LPF) will be used in the adaptive filter
block. Also, only the programmed values for Gain B in the
HD Sharpness Filter Gain, HD Adaptive Filter Gain 1, 2, 3
are applied when needed. The Gain A values are fixed and
cannot be changed.
this mode, a cascade of Filter A and Filter B is used. Both
settings for Gain A and Gain B in the HD Sharpness Filter
Gain, HD Adaptive Filter Gain 1, 2, 3 become active when
needed.
ADV7300A/ADV7301A
1.6
1.5
1.4
1.3
1.2
1.1
1.0
0
FREQUENCY RESPONSE IN SHARPNESS
FILTER MODE WITH Ka = 3 AND Kb = 7
2
FREQUENCY – MHz
4
6
8
10
12