NOT RECOMMENDED FOR NEW DESIGNS
Features
eMI I
NpuT
F
ILTerS
28 V
oLT
I
NpuT
FM-461, FMA-461
AND FMB-461
1.75 To 5 AMP
Attenuation 40 dB from 110 kHz to 50 MHz
• Operating temperature -55° to +85°C
• 1.75 to 5 A throughput current
• Transient suppression
• Nominal 28 V input, 0 V to 40 V operation
• Compliant to MIL-STD-461C CE-03
I
NpuT
(V)
0 - 40
0 - 40
0 - 40
I
NpuT
V
oLTage
aND
C
urreNT
MODELS
C
urreNT
(a)
1.75
3.8
5.0
Size (max.): Non-flanged case
H3 - FM-461 2.110 x 1.120 x 0.417 inches (53.59 x 28.45 x 10.59 mm)
H5 - FMA/FMB 2.110 x 1.120 x 0.495 inches (53.59 x 28.45 x 12.57* mm)
Flanged case
K4 - FM-461 2.910 x 1.115 x 0.417 inches (73.91 x 28.32 x 10.59* mm)
K6 - FMA/FMB 2.910 x 1.115 x 0.495 inches (73.91 x 28.32 x 12.57 mm)
Weight:
Maximum – FM-461 38 grams, FMA-461 42 grams, FMB-461 43 grams
Screening: Standard or ES. See screening table for more information.
Description
The FM-461, FMA-461, and FMB-461 EMI filter modules have
been specifically designed to reduce the input line reflected ripple
current of Interpoint’s MTO, MTW, MHE, MLP, and MFW Series
of DC/DC converters. They are intended for use in applications of
high frequency (100 kHz) switch-mode DC/DC converters which
must meet MIL-STD-461C levels of conducted power line noise.
These filters are built using thick-film hybrid technology and are
sealed in metal packages for military, aerospace, and other high-
reliability applications. See Section B8, cases H3, H5, K4, and
K6 for dimensions. See Section C2 for screening options.
F
ILTer
o
peraTIoN
A fast-reacting (1 picosecond) transient suppressor clamps
the input voltage at approximately 47 V, protecting the DC/DC
converter from line induced transients.
The filters are rated to operate, with no degradation of perfor-
mance, over the temperature range of –55°C to +85°C (as
measured at the baseplate). Above 85°C, input voltage and
current must be derated as specified in “Derating” on the
following page. The maximum power dissipation of the filters at
maximum input current represents a power loss of less than 3%
at typical input voltage.
MIL-STD N
oISe
M
aNageMeNT
When used in conjunction with Interpoint’s DC/DC converters
(see connection diagram, Figure 2), the input ripple current will
be reduced by 40 dB within the frequency band of 100 kHz to 50
MHz. This gives the filter/converter combination a performance
which exceeds the CE03 test limit of MIL-STD-461C. The CE03
performance of a model MHE2805S converter with and without
the FM-461 filter is shown in Figures 6 and 7.
L
ayouT
r
equIreMeNTS
The case of the filter must be connected to the case of the
converter through a low impedance connection to minimize EMI.
Crane Aerospace & Electronics
Electronics Group (Interpoint Brand)
PO Box 97005 • Redmond WA 98073-9705
425.882.3100 • power@crane-eg.com
www.interpoint.com
Page 1 of 9
FM/A/B Rev C 20100212
INTERPOINT [ INTERPOINT CORPORATION COMPANY ]
