ADV7341BSTZ Analog Devices Inc, ADV7341BSTZ Datasheet - Page 64

• 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

ADV7340/ADV7341
ED/HD SHARPNESS FILTER AND ADAPTIVE
FILTER CONTROLS
Subaddress 0x40; Subaddress 0x58 to Subaddress 0x5D
There are three filter modes available on the ADV7340/ADV7341:
a sharpness filter mode and two adaptive filter modes.
ED/HD Sharpness Filter Mode
To enhance or attenuate the Y signal in the frequency ranges
shown in Figure 72, the ED/HD sharpness filter must be
enabled (Subaddress 0x31, Bit 7) and the ED/HD adaptive filter
must be disabled (Subaddress 0x35, Bit 7).
To select one of the 256 individual responses, the corresponding
gain values, which range from –8 to +7 for each filter, must be
programmed into the ED/HD sharpness filter gain register at
Subaddress 0x40.
ED/HD Adaptive Filter Mode
The ED/HD adaptive filter (Threshold A, Threshold B, and
Threshold C) registers, the ED/HD adaptive filter (Gain 1,Gain 2,
and Gain 3) registers, and the ED/HD sharpness filter gain
register are used in adaptive filter mode. To activate the
adaptive filter control, the ED/HD sharpness filter and the
ED/HD adaptive filter must be enabled (Subaddress 0x31, Bit 7,
and Subaddress 0x35, Bit 7, respectively).
SIGNAL
INPUT
STEP

1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
FILTER A RESPONSE (Gain Ka)
FREQUENCY (MHz)
SHARPNESS AND ADAPTIVE FILTER CONTROL BLOCK
Figure 72. ED/HD Sharpness and Adaptive Filter Control Block
1.5
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
Rev. A | Page 64 of 108
FILTER B RESPONSE (Gain Kb)
FREQUENCY (MHz)
The derivative of the incoming signal is compared to the
three programmable threshold values; that is the ED/HD
adaptive filter (Threshold A, Threshold B, and Threshold C)
registers (Subaddress 0x5B, Subaddress 0x5C, and Subaddress
0x5D, respectively). The recommended threshold range is 16 to
235, although any value in the range of 0 to 255 can be used.
The edges can then be attenuated with the settings in the
ED/HD adaptive filter (Gain 1, Gain 2, and Gain 3) registers
(Subaddress 0x58, Subaddress 0x59, and Subaddress 0x5A,
respectively), and the ED/HD sharpness filter gain register
(Subaddress 0x40).
There are two adaptive filter modes available. The mode
is selected using the ED/HD adaptive filter mode control
(Subaddress 0x35, Bit 6) as follows:
•
•
Mode A is used when the ED/HD adaptive filter mode
control is set to 0. In this case, Filter B (LPF) is used in the
adaptive filter block. In addition, only the programmed
values for Gain B in the ED/HD sharpness filter gain
register and ED/HD adaptive filter (Gain 1, Gain 2, and
Gain 3) registers are applied when needed. The Gain A
values are fixed and cannot be changed.
Mode B is used when ED/HD adaptive filter mode control
is set to 1. In this mode, a cascade of Filter A and Filter B is
used. Both settings for Gain A and Gain B in the ED/HD
sharpness filter gain register and ED/HD adaptive filter
(Gain 1, Gain 2, and Gain 3) registers become active when
needed.
1.6
1.5
1.4
1.3
1.2
1.1
1.0
FREQUENCY RESPONSE IN SHARPNESS
0
FILTER MODE WITH Ka = 3 AND Kb = 7
2
FREQUENCY (MHz)
4
6
8
10
12