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PIN
NAME
FUNCTION
18
WS
I
2
S/TDM Word-Select Input with Internal Pulldown to GND
19
CNTL1
Control Input With Internal Pulldown to GND. Input data is latched every RXCLKIN_ cycle (
). CNTL1 is not available in 3-channel mode (BWS = low). Set BWS = high or open (4-channel or
high-bandwidth mode) to use this input. CNTL1 not encrypted when HDCP is on (MAX9281 only)
CNTL1 or RES (“Reserved” from VESA Standard Panel Specification) is mapped to internal bit
DIN27. See the
Reserved Bit (RES)/CNTL1
section.
20
CNTL2
Control Input With Internal Pulldown to GND. Input data is latched every RXCLKIN_ cycle (
). CNTL2 is not available in 3-channel mode (BWS = low). Set BWS = high or open (4-channel or
high-bandwidth mode) to use this input. CNTL2 not encrypted when HDCP is on (MAX9281 only).
CNTL2 is mapped to internal bit DIN28.
22, 39
DVDD
1.8V Digital Power Supply. Bypass DVDD to GND with 0.1µF and 0.001µF capacitors as close as
possible to the device with the smaller value capacitor closest to DVDD.
23, 38
GND
Digital and I/O Ground
24, 37
IOVDD
I/O Supply Voltage. 1.8V to 3.3V logic I/O Power Supply. Bypass IOVDD to GND with 0.1µF and
0.001µF capacitors as close as possible to the device with the smallest value capacitor closest to
IOVDD.
IOVDD sets the voltage levels for all pins except for the LVDS inputs and OUT+/-.
25
RX/SDA
UART Receive/I
2
C Serial Data Input/Output with Internal 30kΩ Pullup to IOVDD. Function is
determined by the state of CONF[1:0] at power-up (
). RX/SDA has an open-drain driver and
requires a pullup resistor.
RX: Input of the serializer’s UART.
SDA: Data input/output of the serializer’s I
2
C Master/Slave.
26
TX/SCL
UART Transmit/I
2
C Serial Clock Input/Output with Internal 30kΩ Pullup to IOVDD. Function is
determined by the state of CONF[1:0] at power-up (
). TX/SCL has an open-drain driver and
requires a pullup resistor.
TX: Output of the serializer’s UART.
SCL: Clock input/output of the serializer’s I
2
C Master/Slave.
27
CONF1
Three-Level Configuration Input. The state of CONF1 latches at power-up or when resuming
from power-down mode (
PWDN
= low). Use 6kΩ (max) for pullup to IOVDD/pulldown to GND.
28
LMN1
Line-Fault Monitor Input 1 (see
for details)
30
OUT-
Inverting CML Coax/Twisted-Pair Serial Output
31
OUT+
Noninverting CML Coax/Twisted-Pair Serial Output
33
LMN0
Line-Fault Monitor Input 0 (see
for details)
34
LFLT
Active-Low Open-Drain Line-Fault Output.
LFLT
has a 60kΩ internal pullup to IOVDD.
LFLT
= low
indicates a line fault.
LFLT
is output high when
PWDN
= low.
35
GPO/HIM
General-Purpose Output/High Immunity Mode Input. Functions as HIM input with internal pulldown
to GND at power-up or when resuming from power-down mode (
PWDN
= low), and switches to GPO
output automatically after power-up.
HIM: Default HIGHIMM bit value is latched at power-up or when resuming from power-down mode
(
PWDN
= low) and is active-high. Connect HIM to IOVDD with a 30kΩ or less pullup resistor to set
high or leave open to set low. HIGHIMM can be programmed to a different value after power-up.
HIGHIMM in the deserializer must be set to the same value.
GPO: Output follows the state of the GPI (or INT) input on the deserializer. GPO is low after power-
up or when
PWDN
is low.
MAX9277/MAX9281
3.12Gbps GMSL Serializers for Coax or
STP Output Drive and LVDS Input
www.maximintegrated.com
Maxim Integrated │
18
Pin Description (continued)