Specifications

Gigabit Multimedia Serial Link Deserializer
with LVDS System Interface
MAX9268
26 _____________________________________________________________________________________
Image-Sensing Applications
For image-sensing applications, connect the FC to the
MAX9268 and set CDS = high for both the GMSL serial-
izer and the MAX9268. The deserializer powers up nor-
mally (SLEEP = 0) and continuously tries to lock to a valid
serial input. Table 10 summarizes both startup cases,
based on the state of the GMSL serializer AUTOS pin.
Case 1: Autostart Mode
After power-up or when PWDN transitions from low to
high, the GMSL serializer locks to a stable input clock
and sends the high-speed data to the MAX9268. The
deserializer locks to the serial data and outputs the video
data and clock.
Case 2: Sleep Mode
After power-up or when PWDN transitions from low to
high, the GMSL serializer starts up in sleep mode. Use the
FC to wake up the serializer by sending a GMSL protocol
UART frame containing at least three rising edges (e.g.,
0x66), at a bit rate no greater than 1Mbps. The low-power
wake-up receiver of the serializer detects the wake-up
frame over the reverse control channel and powers up.
Reset the sleep bit (SLEEP = 0) of the GMSL serializer
using a regular control-channel write packet to power up
the device fully. Send the sleep bit write packet at least
500Fs after the wake-up frame. The GMSL serializer goes
back to sleep mode if its sleep bit is not cleared within
5ms (min) after detecting a wake-up frame.
Applications Information
Error Checking
The MAX9268 checks the serial link for errors and stores
the number of detected decoding errors in the 8-bit
register DECERR (0x0D). If a large number of decoding
errors are detected within a short duration, the deserializer
loses lock and stops the error counter. The deserializer
then attempts to relock to the serial data. DECERR resets
upon successful video link lock, successful readout of
DECERR (through UART), or whenever autoerror reset is
enabled. The MAX9268 does not check for decoding errors
during the internal PRBS test and DECERR is reset to 0x00.
Table 10. Startup Selection for Image-Sensing Applications (CDS = High)
Figure 23. MAX9268 State Diagram, CDS = High (Camera Application)
POWER-ON
IDLE
SERIAL PORT
LOCKING
ALL STATES
POWER-DOWN
OR
POWER-OFF
NO SIGNAL
DETECTED
PWDN = HIGH,
POWER-ON
CONFIG
LINK OPERATING
VIDEO LINK
OPERATING
VIDEO LINK
LOCKED
VIDEO LINK
UNLOCKED
PRBSEN = 0
PRBSEN = 1
VIDEO LINK
PRBS TEST
CONFIG LINK
UNLOCKED
CONFIG LINK
LOCKED
SIGNAL
DETECTED
PROGRAM
REGISTERS
PWDN = LOW OR
POWER-OFF
(REVERSE
CHANNEL
ACTIVE)
CASE
AUTOS
(GMSL SERIALIZER)
GMSL SERIALIZER
POWER-UP STATE
MAX9268 POWER-UP
STATE
LINK STARTUP MODE
1 Low Serialization enabled
Normal
(SLEEP = 0)
Autostart
2 High
Sleep mode
(SLEEP = 1)
Normal
(SLEEP = 0)
GMSL serializer is in sleep mode.
Wake up the serializer through the
control channel (FC attached to
MAX9268).