MAX9257AGTL+T Maxim Integrated, MAX9257AGTL+T Datasheet - Page 31
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MAX9257AGTL+T
Manufacturer Part Number
MAX9257AGTL+T
Description
Serializers & Deserializers - Serdes Prog Serializer / Deserializer
Manufacturer
Maxim Integrated
Type
Serializerr
Datasheet
1.MAX9258AGCMV.pdf
(53 pages)
Specifications of MAX9257AGTL+T
Rohs
yes
Data Rate
840 Mbit/s
Input Type
LVCMOS
Output Type
LVDS
Number Of Inputs
18
Number Of Outputs
1
Operating Supply Voltage
1.7 V to 3.6 V
Operating Temperature Range
- 40 C to + 105 C
Package / Case
TQFN-40 EP
Maximum Operating Temperature
+ 105 C
Minimum Operating Temperature
- 40 C
Mounting Style
SMD/SMT
Supply Voltage - Max
3.6 V
Supply Voltage - Min
1.71 V, 3 V
Figure 22. Control Channel Closing Due to STO Timeout
The ETO (end timeout) timer closes the control channel if
the ECU stops communicating for the ETO timeout period.
Configure register REG3[7:4] for both the MAX9257A and
the MAX9258A to select the divide ratio (ETODIV) for the
ETO clock as a function of the pixel clock
timeout period is determined by counter bits REG3[3:0]
that increment once every ETO clock period. Write to
REG3[3:0] to determine the counter end time. The ETO
counter counts to the pro grammed ETOCNT + 1. Any
ECU activity resets the ETO timer. When the ECU stops
transmitting data for the ETO timeout period, the control
channel closes
For example:
If the pixel clock frequency is set to 16MHz, ETODIV is
set to 1010 (ETODIV = 1024), and ETOCNT is set to 1001
(ETOCNT = 9), the ETO timer counts with the 15.625kHz
ETO clock (16MHz/1024) internally until it reaches 10 and
timer expires. The t
t
ETO
=
VSYNC_IN
(Figure
f
SDI/O
DOUT_
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CLK
CCEN
ETO
1
RX
Fully Programmable Serializer/Deserializer
TX
T1 = TIME TO ENTER CONTROL CHANNEL
T2 = STO TIMEOUT PERIOD
T3 = CONTROL CHANNEL EXIT TIME DUE TO STO
HSK = HANDSHAKING BETWEEN THE MAX9257 AND THE MAX9258
×
is equal to t
23).
ETODIV (ETOCNT 1)
VIDEO
×
T
x 1024 x 10 = 640Fs.
T1
(Table
+
ETO Timer
with UART/I
25). The
T2
FROZEN
Table 25. ETO Clock Divide Ratio
The default value for ETODIV is 1024 while the default
value for ETOCNT is 0. That means the ETO timeout
period is equal to 1,024 pixel clock cycles.
MAX9257A/MAX9258A
REG3[7:4]
00XX
2
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
C Control Channel
HSK
T3
VIDEO
ETODIV
16,384
32,768
1024
2048
4096
8192
128
256
512
16
16
32
64