Document 153
RS-232 EMI Filter Modules
Coilcraft’s EMI filter modules are an easy, effective way
to eliminate the problems of stray electromagnetic inter-
ference (EMI) in signal cables running between poorly
filtered equipment.
Available in DB-25, -15 and -9 versions, the modules
plug between an RS-232 cable and an input or output
port. Common mode magnetics filter all lines including
the frame ground, attenuating EMI over the critical
30 - 300 MHz range while leaving data signals totally
undisturbed.
Comparable EMI filters for circuit board mounting are also
available.
A
Male DB
Female DB
B
2.25
57,15
2.25
57,15
2.25
57,15
C
0.67
17,02
0.67
17,02
0.67
17,02
Pins
9
15
25
DLFC9
A
1.35
34,29
1.65
41,91
2.16
54,86
DLFC15
DLFC25
B
C
Typical Attenuation
1
-10
Attenuation (dB)
Differential Mode
0
Co
mm
10
on
Mo
de
20
30
0.1
1
10
100
1000
Frequency (MHz)
1. Measured on HP 8753D network analyzer. Ref: 50 Ohms.
2. Operating temperature range –40°C to +85°C.
3. Electrical specifications at 25°C.
Specifications subject to change without notice.
Document 153
Revised 11/26/02
© Coilcraft, Inc. 2009
COILCRAFT [ Coilcraft lnc. ]
