ELM634
9600bps miniLIN Monitor
Description
LIN or ‘Local Interconnect Network’ is a low cost
and relatively simple networking system that is used
predominantly in the automotive world. Recently, it
has been gaining in popularity with proposals to use
it in major appliances as well. For more information,
visit the LIN web site (http://www.lin-subbus.de/).
The ELM634 is a monitoring device designed
for troubleshooting LIN bus systems. It is capable of
continually monitoring a LIN network, translating the
LIN messages to standard ASCII characters, and re-
transmitting them to an RS232 system (personal
computer or PDA) for display and possibly for
analysis. The synchronizing, data formatting, and
checksum calculations are all done for you by the
ELM634.
The LIN specification has recently been updated
to revision 2.0, incorporating several improvements.
The ELM634 has been updated to be compatible
with this new specification, as well as the previous
ones.
V
DD
XT1
Features
• Low power CMOS design
• Crystal controlled for accuracy
• Standard ASCII character output
• Special power-on monitor mode
• Permanently set to a 9600bps LIN rate
• High speed (57600 baud) RS232 interface
• Works with LIN1.x and LIN2.0
Connection Diagram
PDIP and SOIC
(top view)
1
2
3
4
8
7
6
5
V
SS
LIN
RS232Tx
RS232Rx
Applications
• LIN logic probes
• Diagnostic PC interfaces
• Instruction triggered (breakpoint) devices
• Educational or training devices
XT2
Rxmode
Block Diagram
XT1
2
3.58MHz
3
XT2
Timing
RS232Tx
RS232Rx
6
5
RS232
Interface
Formatting
and
Control
LIN
Interface
7
LIN
Rxmode
4
ELM634DSB
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