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The serializer reverse channel mode is not available for
500µs/1.92ms after the reverse control channel mode is
changed through the serializer/deserializer’s HIGHIMM
bit setting respectively. The user must set GPO/HIM or
the HIGHIMM bits to the same value for proper reverse
control channel communication.
In high-immunity mode, Set HPFTUNE = 00 in the equal
-
izer, if the serial bit rate = [RXCLKIN_ x 30 (BWS =
low or open) or 40 (BWS = high)] is larger than 1Gbps
when BWS is low or high. When BWS = open, set
HPFTUNE = 00 when the serial bit rate is larger than
2Gbps. In addition, use 47nF AC-coupling capacitors.
Note that legacy reverse control channel mode may not
function when using 47nF AC-coupling capacitors.
By default, high immunity mode uses a 500kbps bit rate.
Set REVFAST =1 (D7 in register 0x1A in the serializer and
register 0x11 in the deserializer) in both devices to use a
1Mbps bit rate. Certain limitations apply when using the
fast high-immunity mode (
Figure 38. 2:1 Coax Splitter Connection Diagram
Figure 39. Coax Connection Diagram
Table 10. CONF[1:0] Input Map
CONF1
CONF0
CONTROL CHANNEL MODE
(I2CSEL)
SPREAD ENABLE
(SSEN)
DATA RATE SELECT
(DRS)
Low
Low
UART (0)
Disabled (0)
High rate (0)
Low
High
UART
Disabled
Low rate (1)
High
Low
UART
Enabled (1)
High rate
High
High
UART
Enabled
Low rate
Mid
Low/Mid
I
2
C (1)
Disabled
High rate
Low
Mid
I
2
C
Disabled
Low rate
High
Mid
I
2
C
Enabled
High rate
Mid
High
I
2
C
Enabled
Low rate
OUT+
OUT-
OPTIONAL
COMPONENTS
FOR INCREASED
POWER-SUPPLY
REJECTION
IN+
IN-
IN+
IN-
MAX9277/
MAX9281
GMSL
DESERIALIZER
GMSL
DESERIALIZER
OUT+
OUT-
IN+
OPTIONAL COMPONENTS
FOR INCREASED POWER-SUPPLY
REJECTION
IN-
AVDD
50
Ω
MAX9277/
MAX9281
GMSL
DESERIALIZER
MAX9277/MAX9281
3.12Gbps GMSL Serializers for Coax or
STP Output Drive and LVDS Input
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