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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