max9247etmt Maxim Integrated Products, Inc., max9247etmt Datasheet - Page 10

• Manufacturer Part Number: max9247etmt
• Description: Max9247 27-bit, 2.5mhz-to-42mhz Dc-balanced Lvds Serializer
• Manufacturer: Maxim Integrated Products, Inc.

27-Bit, 2.5MHz-to-42MHz
DC-Balanced LVDS Serializer
Figure 8. Peak-to-Peak Output Offset Voltage
The MAX9247 DC-balanced serializer operates at a
2.5MHz-to-42MHz parallel clock frequency, 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 (see Table 1). Control inputs are mapped to 19
bits and encoded with 1 overhead bit, EN0, also result-
ing in a 20-bit serial word. Encoding reduces EMI and
Table 1. Serial Video Phase Word Format
Bit 0 is the LSB and is serialized first. EN[1:0] are encoding bits. S[17:0] are encoded symbols.
Table 2. Serial Control Phase Word Format
Bit 0 is the LSB and is serialized first. C[8:0] are the control inputs.
10
EN0
E N 0
0
((OUT+) + (OUT-)) / 2
0
______________________________________________________________________________________
EN1
C0
1
1
OUT+
OUT-
S0
C0
2
2
S1
C0
3
3
Detailed Description
S2
C1
4
4
S3
C1
5
5
S4
C1
6
6
V
OS(P-P)
S5
C2
7
7
S6
C2
8
8
S7
C2
9
9
10
S8
C3
10
maintains DC balance across the serial cable. Two
transition words, which contain a unique bit sequence,
are inserted 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 (see Table 2). At the deserial-
izer, 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.
11
S9
C3
11
S10
12
C3
12
S11
V
13
C4
13
OS(P-P)
S12
C4
14
14
S13
C4
15
15
S14
16
C5
16
S15
C6
17
17
S16
C7
18
18
S17
C8
19
19