MAX7469UTP Maxim Integrated, MAX7469UTP Datasheet - Page 14

• Manufacturer Part Number: MAX7469UTP
• Description: Video ICs
• Manufacturer: Maxim Integrated

HDTV Continuously Variable
Anti-Aliasing Filters
Figure 8. Basic Read Sequence
selected in the command byte. Figure 8 shows a basic
read sequence.
Note: The master has to write a command byte,
requesting to read the control/status or frequency reg-
ister, to the slave (MAX7469/MAX7470) before the mas-
ter can read the contents of the selected register.
The MAX7469/MAX7470 store their status in an 8-bit
register that can be read back by the master. The indi-
vidual bits of the control/status register are summarized
in Tables 4 and 5. The power-on default value of this
register is 03h.
The frequency response (-3dB passband edge) of the
MAX7469/MAX7470 can be continuously varied in 256
linear steps by changing the codes in the frequency reg-
ister (Table 6). See the Command Byte ( Write Cycle) sec-
tion for a write sequence to update the frequency register.
Table 4. Control/Status Register
Table 6. Frequency Register Setting for Different Video-Signal Formats
14
Standard Definition (Interlaced)
Standard Definition (Progressive)
High-Definition Low Bandwidth
High-Definition High Bandwidth
SCL (CONT)
SDA (CONT)
DIRECTION
DIRECTION
S7
SDA
SDA
VIDEO-SIGNAL FORMAT
_______________________________________________________________________________________
SDA
SCL
START
S6
CONTROL/STATUS REGISTER
1
S5
Sr
0
IN TO MAX7469/MAX7470
1
S4
0
0
1
Control/Status Register
S3
0
F7
0
0
1
1
Frequency Register
0
IN
1
S2
F6
1
1
0
1
A1
0
F5
1
0
0
1
A0
S1
A1
F4
0
1
1
1
A0
S0
OUT
F3
ACK
1
1
1
1
R/W
C7
F2
ACK
0
0
0
1
1
Table 5. Control/Status Register Bit
Description
C6
0
F1
D7
0
1
0
1
BIT
S7
S6
S5
S4
S3
S2
S1
S0
C5
0
F0
D6
0
0
0
1
C4
1
CODE NO.
D5
0 = component input signal selected (default).
1 = composite input signal selected.
0 = internal sync enabled (default).
1 = external sync enabled.
0 = external sync: positive polarity (default).
1 = external sync: negative polarity.
0 = normal operation mode (default).
1 = power-down mode.
0 = filters enabled (default).
1 = bypass mode—no filtering.
0 = clamp voltage for IN1 set to low (default).
1 = clamp voltage for IN1 set to high.
0 = clamp voltage for IN2 set to low.
1 = clamp voltage for IN2 set to high (default).
0 = clamp voltage for IN3 set to low.
1 = clamp voltage for IN3 set to high (default).
IN
220
255
40
90
C3
OUT
0
D4
C2
0
D3
1/0
C1
APPROXIMATE FREQUENCY
D2
DESCRIPTION
C0
1
D1
(-3dB) MHz
34 (default)
ACK
OUT
D0
10
15
30
ACK
IN
STOP