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FMD28-461 Datasheet, PDF (1/8 Pages) Interpoint Corporation Company – EMI INPUT FILTERS 28 & 270 VOLT INPUT
Crane Aerospace & Electronics Power Solutions
FMD28-461 EMI Input Filters
28 Volt input – 7 Amp
Features
Attenuation to 50 dB at 500 kHz
• Operating temperature -55° to +125°C
• Nominal 28 V input, 0 to 50 V operation
• Transient rating to 100 V for 100 ms
• Up to 7 A throughput current
• Compliant to MIL-STD-461C, CE03
• Compatible with MIL-STD-704 A-E 28 VDC power bus
Description
The FMD28 Series™ EMI filters are specifically designed to
reduce the reflected input ripple current of Interpoint’s high
frequency DC/DC converters. FMD filters minimize electro-
magnetic interference (EMI) for the MOR, MFL, MTR, MHV,
MHF+, MHF, MTO and MHE Series of converters. These filters
are intended for use in 28 volt applications which must meet
MIL-STD-461C CE03 levels of conducted emissions. One filter
can be used with multiple converters up to the rated output
current of the filter.
Input Ripple and EMI
Switching DC/DC converters naturally generate two noise
components on the power input line: differential noise and
common mode noise. Input ripple current refers to both of these
components. Differential noise occurs between the positive input
and input common. Most Interpoint converters have an input filter
that reduces differential noise which is sufficient for many appli-
cations. Common mode noise occurs across stray capacitances
between the converter’s power train components and the base-
plate (bottom of the package) of the converter.
Where low noise currents are required to meet CE03 of
MIL-STD-461C a power line filters reduces the common mode
and differential noise generated by the converters. FMD28-
461 filters reduce input ripple current by as much as 50 dB
at 500 kHz when used in conjunction with Interpoint’s DC/DC
converters.
Place the filter as close as possible to the converter for optimum
performance. The baseplates of the filter and the converter
should be connected with the shortest and widest possible
conductors.
Transients
A transient of 100 V for up to 100 ms with a 0.5 ohm source
impedance will not damage the filter.
Operation over Temperature
The FMD28-461 Series filters are rated for full power opera-
tion from -55°C to +125°C case temperature. Current is derated
linearly to zero at +135°C case temperature.
Insertion Loss
The maximum dc insertion loss at full load and nominal input
voltage represents a power loss of less than 1.3%.
Packaging
FMD28-461 filters are sealed in metal hermetic, down-leaded
packages (case J4). Also available in a side-leaded package
(case U).
Crane Aerospace & Electronics
Electronics Group (Interpoint Brand)
PO Box 97005•Redmond WA 98073-9705
425.882.3100 • power@crane-eg.com
www.interpoint.com
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FMD28 Rev A - 20090909