Crane Aerospace & Electronics Power Solutions
FMD28-461 eMi input Filters
28 Volt input – 7 aMp
Features
•
Operating temperature -55° to +125°C
•
Transient rating to 100 V for 100 ms
•
Up to 7 A throughput current
•
Compliant to MIL-STD-461C, CE03
attenuation to 50 dB at 500 kHz
•
Nominal 28 V input, 0 to 50 V operation
•
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.
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.
t
RansIents
A transient of 100 V for up to 100 ms with a 0.5 ohm source
impedance will not damage the filter.
O
peRatIOn OveR
t
eMpeRatuRe
I
nput
R
Ipple 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.
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.
I
nseRtIOn
l
Oss
p
ackagIng
The maximum dc insertion loss at full load and nominal input
voltage represents a power loss of less than 1.3%.
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
Page 1 of 8
FMD28 Rev C - 20100226
Crane Aerospace & Electronics Power Solutions
FMD28-461 eMi input Filters
28 Volt input – 7 aMp
Operating COnditiOns and
CharaCteristiCs
input Voltage range
•
0 to 50 VDC continuous
•
Transient +100 V for 100 ms
meChaniCal and envirOnmental
size (maximum)
•
Case J4, FMD28-461
‣
2.720 x 1.350 x 0.505 inches (69.09 x 34.29 x 12.83 mm)
‣
Shown on page 1 in Case J4 (down-leaded).
•
Case U, FMD28-461SL
3.005 x 1.505 x 0.400 inches (76.33 x 38.23 x 10.16 mm)
Weight (maximum)
•
Case J4: 55 grams typical
•
Case U: 77 grams typical
lead soldering temperature (10 sec per lead)
•
300°C
storage temperature range (case)
•
-65°C to +150°C
case operating temperature (t
c
)
•
-55°C to +125°C full power
•
-55°C to +135°C absolute
isolation
•
100 megohm minimum at 500 VDC
Derating input/output current
•
Linearly from 100% at 125°C to 0% at 135° C
screening
FMD28 is offered with 125°C Standard and /ES, non-QML
screening. See Standard and /ES (non-QML) screening tables for
more information on page 8.
EMI FILTER
+Vin
Case
Output
Input
Common Common
+Vout
DC/DC CONVERTER
+Vin
+Vout
RL
Case
Output
Input
Common Common
Chassis
ground
Multiple units
allowed up to
rated output
current of filter
RL
The case ground connection between the filter and the converter should be as
low an impedance as possible to minimize EMI. Direct contact of baseplate to
chassis ground provides the lowest impedance.
F
IguRe
1: c
OnnectIOn
d
IagRaM
Positive
Input
Positive
Output
Input
Common
Output
Common
FMD28-461
F
IguRe
2: FMd28-461 s
cheMatIc
www.interpoint.com
Page 2 of 8
FMD28 Rev C - 20100226
Crane Aerospace & Electronics Power Solutions
FMD28-461 eMi input Filters
28 Volt input – 7 aMp
pin out DoWn-leaDeD MoDel
pin
1
2
3
4
5
Positive Input
Designation
Squared corner and dot on top
of package indicate pin one.
Positive Output
Case Ground
1
Input Common
Output Common
1
2
BOTTOM VIEW
FMD28-461
5
See case J4 for dimensions.
4
3
Note
1. Although the down-leaded packages can be
connected to chassis ground with the case
ground lead, direct contact of the base plate to
chassis improves EMI performance.
F
IguRe
3: p
In
O
ut
FMd28-461
pin out siDe-leaDeD MoDels
pin
1
Designation
1, 2, 3
4, 5, 6
10, 11, 12
—
7, 8, 9
Positive Input
Angled corner and cover marking indicate pin one.
TOP VIEW
FMD28-461
Outline shown is case U, pin out is the same
for all cases. See cases U, V, W, Y, and Z
for dimensions.
Input Common
Output Common
Positive Output
Case Ground
2
1
2
3
4
5
12
11
10
9
8
7
Notes
1. All pins must be connected.
2. The baseplate is the only case ground connection and
should directly contact chassis ground.
6
F
IguRe
4: p
In
O
ut
FMd28-461sl
www.interpoint.com
Page 3 of 8
FMD28 Rev C - 20100226
Crane Aerospace & Electronics Power Solutions
FMD28-461 eMi input Filters
28 Volt input – 7 aMp
MoDel nuMBering key
Base Model
Input Voltage
FMD
28 - 461
SL / ES
MIL-STD-461 Reference
Case/Lead Option*
Screening
(Standard screening has no designator
in this position.)
*Case/Lead Option:
For drawings and dimensions see cases J4 (case option is
left blank) and U (case option is SL).
O
n the lines belOw
,
enter One selectiOn frOm each categOry
tO determine the mOdel number
.
category
FMD28
Base MoDel anD
input Voltage
MoDel selection
-461
Mil-stD-461 reFerence
_______
case/leaD
option
1
Down-leaded
(leave blank)
sl (case u,
side-leaded)
/
______
screening
2
standard (leave blank)
es
selection
“FMD28” is the
only available
selection
“-461” is the only
available selection
Notes:
1. Case J4 is the standard, down-leaded case. Leave the option blank for case J4. Refer to the case drawings on pages 6 and 7 for other case options.
2. Leave blank for standard screening. Use “ES” for “ES” screening. See the table on page 8 for more information.
www.interpoint.com
Page 4 of 8
FMD28 Rev C - 20100226
Crane Aerospace & Electronics Power Solutions
FMD28-461 eMi input Filters
28 Volt input – 7 aMp
Electrical Characteristics: 25°C T
C
, nominal Vin, unless otherwise specified.
MODEL
paRaMeteR
Input vOltage
nOIse ReJectIOn
dc ResIstance (R
dc
)
at MaXIMuM cuRRent
1
capacItance
1
Output vOltage
Output cuRRent
pOWeR dIssIpatIOn
at MaXIMuM cuRRent
1
cOndItIOns
tRansIent 100
ms
1,
2
500
k
h
z
1 Mh
z
t
c
= 125°c
t
c
= 25°c
cOntInuOus
MIN
0
-100
50
45
—
—
FMD28-461
TYP
28
—
60
55
—
—
20,000
V
OUT
= V
IN
- I
IN
(R
DC
)
—
—
—
—
—
—
7
6.0
7.4
MAX
50
1
100
—
—
0.12
0.15
unIts
VDC
V
dB
Ω
pF
VDC
A
W
anY pIn tO case
steadY state
steadY state
t
c
= 125°c
1
t
c
= 25°c
Note
1. guaranteed by design, not tested.
2. 0.5 ohm source impedance
www.interpoint.com
Page 5 of 8
FMD28 Rev C - 20100226