14
62 COM2 RI#
RI#
64 GND
GND
GND
GND
Table 1.4.1-1 Signal Description for COM
1.4.2 Schematic Guidelines
As for general ESD protection, the transmitters/receivers of RS-232/422/485 in CPU
board can meet the requirement, and users don’t implement extra ESD components.
Considering EMI, the bead and capacitors are the recommendatory solution. For
placement concern, EMI solution should be close to connector.
Figure 1.4.2-1 EMI demonstration for RS-232 Application
I/O Board
EMI Solution
CPU Board
CN
B22
600_100MHz 0.3A
0402
B23
600_100MHz 0.3A
0402
B24
600_100MHz 0.3A
0402
B25
600_100MHz 0.3A
0402
DCD#
B26
600_100MHz 0.3A
0402
B27
600_100MHz 0.3A
0402
DSR#
RTS#
RXD
B28
600_100MHz 0.3A
0402
DTR#
CTS#
TXD
RI#
B29
600_100MHz 0.3A
0402
CN11
DSUB_9(M)H
5
9
4
8
3
7
2
6
1
10
11
GND_Chasis