HMP8117CN Intersil Corporation, HMP8117CN Datasheet - Page 37

• Manufacturer Part Number: HMP8117CN
• Description: NTSC/PAL Video Decoder
• Manufacturer: Intersil Corporation

NO.
NO.
NO.
NO.
NO.
BIT
BIT
BIT
BIT
BIT
7-6
4-0
7-6
5-0
7-0
7-4
3-0
7-0
5
Reserved
Select PFG Enable
PFG
Reserved
MV Stripe Gate
Reserved
Reserved
Device Revision
FUNCTION
FUNCTION
FUNCTION
FUNCTION
FUNCTION
37
Set to 00
Set to “1” to enable the recommended PFG value in bits 4-0 below.
Programmable Fractional Gain (PFG). When enabled by bit 5, changes the loop gain (response
time) of the AGC logic. Slower values provide some noise immunity to input signals with poor
sync/back-porch characteristics. Recommend using the slowest PFG value of 00001
optimum performance. (Thus the recommended 8-bit register value = 21
The 5-bit PFG value has a fractional representation as: 2
Sample PFG values:
00000
00001
01100
10000
11111
Set to 00
Defines the start of the gate for MV Color Stripe detection in 4xF
prior to the chroma burst. Default value of 010100
100000
Set bit 5 to “1” for optimum performance.
Defines the amount of hysteresis in the AGC logic. Larger hysteresis values stabilize the AGC
with poor quality input signals. For example:
0000
1000
1111
Set to 0000
This 8-bit register specifies the device revision number. Data written to this read-only register is
ignored. The production baseline revision number is 01
B
B
B
B
B
B
B
B
= No Hysteresis
= Default Hysteresis
= Maximum Hysteresis (Recommended hysteresis value)
B
: Gain = 0.0000 (freezes AGC at current value)
: Gain = 0.0625 (slowest AGC response time -- recommended PFG)
: Gain = 0.7500 (default)
: Gain = 1.0000
: Gain = 1.9375 (fastest AGC response time -- not recommended)
B
B
(20
TABLE 63. PROGRAMMABLE FRACTIONAL GAIN
for proper operation.
for proper operation.
B
H
for proper operation.
) for PAL.
TABLE 66. AGC HYSTERESIS
TABLE 67. DEVICE REVISION
TABLE 64. MV STRIPE GATE
TABLE 65. RESERVED
SUB ADDRESS = 7F
SUB ADDRESS = 50
SUB ADDRESS = 51
SUB ADDRESS = 52
SUB ADDRESS = 53
HMP8117
DESCRIPTION
DESCRIPTION
DESCRIPTION
DESCRIPTION
DESCRIPTION
H
H
H
H
H
B
(14
H
H
) is valid for NTSC. Recommend
.
0
. 2
-1
SC
2
-2
counts. The gate should start
2
-3
2
-4
H
).
B
for
(Use F0
(Use 01
(Use 22
010100
(Use 1
RESET
01100
RESET
RESET
RESET
RESET
STATE
STATE
STATE
STATE
STATE
1000
0000
00
00
02
01
0
B
B
B
H
H
B
B
B
B
H
H
H
B
)
)
)
)