Detailed description, Table 1. serial video phase word format, Table 2. serial control phase word format – Rainbow Electronics MAX9217 User Manual
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MAX9217
27-Bit, 3MHz-to-35MHz
DC-Balanced LVDS Serializer
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Detailed Description
The MAX9217 DC-balanced serializer operates at a
parallel clock frequency of 3MHz to 35MHz, serializing
18 bits of parallel video data RGB_IN[17:0] when the
data enable input DE_IN is high, or 9 bits of parallel
control data CNTL_IN[8:0] when DE_IN is low. The
RGB video input data are encoded using 2 overhead
bits, EN0 and EN1, resulting in a serial word length of
20 bits (Table 1). Control inputs are mapped to 19 bits
and encoded with 1 overhead bit, EN0, also resulting in
a 20-bit serial word. Encoding reduces EMI and main-
tains DC balance across the serial cable. Two transition
words, which contain a unique bit sequence, are insert-
ed at the transition boundaries of video-to-control and
control-to-video phases.
Control data inputs C0 to C4 are mapped to 3 bits each
in the serial control word (Table 2). At the deserializer,
2 or 3 bits at the same state determine the state of the
recovered bit, providing single bit-error tolerance for
C0 to C4. Control data that may be visible if an error
occurs, such as VSYNC and HSYNC, can be connect-
ed to these inputs. Control data inputs C5 to C8 are
mapped to 1 bit each.
OUT-
OUT+
((OUT+) + (OUT-)) / 2
V
OS(P-P)
V
OS(P-P)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
EN0
EN1
S0
S1
S2
S3
S4
S5
S6
S7
S8
S9
S10
S11
S12
S13
S14
S15
S16
S17
Figure 8. Peak-to-Peak Output Offset Voltage
Bit 0 is the LSB and is serialized first. EN[1:0] are encoding bits. S[17:0] are encoded symbols.
Table 1. Serial Video Phase Word Format
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
E N 0
C0
C0
C0
C1
C1
C1
C2
C2
C2
C3
C3
C3
C4
C4
C4
C5
C6
C7
C8
Bit 0 is the LSB and is serialized first. C[8:0] are the control inputs.
Table 2. Serial Control Phase Word Format