DESCRIPTION
The FMSA-461 EMI filter module has been designed as a
companion for Interpoint MSA flyback power converters. Multiple
MSA power converters can be operated from a single filter provided
the total power line current does not exceed the filter maximum
rating. The FMSA filter will reduce the MSA's power line reflected
ripple current to within the limit of MIL-STD-461C, Method CE03, as
shown in the example of Figures 4 and 5.
The FMSA is fabricated using thick film hybrid technology and is
sealed in a metal package for military, aerospace and other appli-
cations requiring EMI suppression. The filter uses only ceramic
capacitors for reliable high temperature operation.
O
PERATION
The MSA power converter has an internal 2 F capacitor across its
input power terminals. When the MSA and FMSA filters are used
together, this capacitor becomes part of the filter and forms its final
LC output section. When 2 or 3 MSAs are used with a single filter,
this capacitor becomes 4 F or 6 F respectively, rather than 2 F,
improving the rejection vs. frequency.
The FMSA filter can also be used with other types of Interpoint
power converters (MHF, MHF+, MHE, MHD, and DCH series) to
comply with CE03. For MHF, MHF+, MHD, and MHE models, the
converter has an LC type line filter such that an inductor is seen
looking into its positive input terminal. For these converters, it is
necessary to terminate the filter with a capacitor to insure uncondi-
tionally stable operation. A capacitor across the filter output termi-
nals of greater than 4F or the optional damping circuit shown on
the connection diagram will be adequate for stable operation. No
capacitor is required for MSA, or DCH models.
O
PTIONAL
D
AMPING
C
IRCUIT
The optional damping circuit (Figure 2) can be used to prevent filter
overshoot caused by MIL-STD-704A 80 V, or other, transients
having rise times of less than 200 Sec. This damping can be alter-
nately provided with a 1.50 resistor in series with the filter positive
input where the additional line loss can be tolerated. For transients
with rise times of greater than 200 sec, there is no overshoot and
the damping circuit is not required.
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.
EMI I
NPUT
F
ILTER
28 V
OLT
I
NPUT
FMSA EMI FILTER
0.8 AMP
F
EATURES
55C to +125C operation
50 dB minimum attenuation
at 500 kHz
Compliant to MIL-STD-461C, CE03
Compatible with MIL-STD-704E
DC power bus
Size (max.): 0.980 x 0.805 x 0.270 (24.89 x 20.45 x 6.86 mm)
See cases "A maximum dimensions" and "A1" for dimensions.
Weight:
10.3 grams typical, 11.5 grams maximum
Screening: Standard, ES or Class H
See "QA Screening: Class H, QML" for more information.
MODEL
FMSA-461
0.8 amp
ABSOLUTE MAXIMUM RATINGS
TYPICAL CHARACTERISTICS
RECOMMENDED OPERATING CONDITIONS
Input Voltage
0 to 50 VDC continuous
80 V for 100 ms transient
Lead Soldering Temperature (10 sec per lead)
300C
Storage Temperature Range (Case)
65C to +150C
FMSA EMI FILTER
0.8 AMP
Input Voltage Range
16 to 40 VDC continuous
Case Operating Temperature (Tc)
55C to +125C full power
Derating Input/Output Current
Derate linearly from 100% at 100C to 0.60
amps at 125C case. Above 125C derate to 0%.
Electrical Characteristics: 25C Tc, nominal Vin, unless otherwise specified.
EMI I
NPUT
F
ILTERS
Capacitance
0.045 F max, any pin to case
Isolation
100 megohm minimum at 500 V
Any pin to case, except case pin
2 F
6800 pF
500 V
6800 pF
500 V
Positive
Input
Input
Common
Positive
Output
Output
Common
FMSA-461
>285 H
6 H
2 F
0.014 F / 500 V
20
20
0.65
6 H
0.014 F / 500 V
0.014 F / 500 V
x 2
x 2
F
IGURE
1: S
CHEMATIC
T
YPICAL
V
ALUES
FMSA-461
PARAMETER
CONDITIONS
MIN TYP
MAX
UNITS
INPUT VOLTAGE
CONTINUOUS
0
28
40
VDC
TRANSIENT
1
, 100 ms
--
--
80
V
INPUT CURRENT
1
--
--
0.80
A
NOISE REJECTION
500 kHz
50
--
--
dB
1 MHz
50
--
--
NOISE REJECTION
5 MHz
45
--
--
dB
DC RESISTANCE (R
DC
)
TC = 25C
--
--
1.2
OUTPUT VOLTAGE
STEADY STATE
V
OUT
= V
IN
- I
IN
(R
DC
)
VDC
OUTPUT CURRENT
STEADY STATE (<100C CASE)
--
--
0.80
A
INTERNAL POWER
DISSIPATION
MAXIMUM CURRENT
--
--
0.96
W
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.
Notes:
1. Guaranteed by design, not tested.
PIN OUT
MODEL NUMBERING KEY
Squared corner and
dot on top of cover
indicate pin one.
1
3
8
4
7
2
6 5
BOTTOM
VIEW
FMSA
FMSA - 461 / 883
Base Model
MIL-STD-461 Reference
Screening
(Standard screening has no designator
in this position.)
EMI I
NPUT
F
ILTERS
See cases "A maximum dimensions" and "A1" for dimensions.
Pin
Designation
1
Positive Input
2, 3
Positive Output
4
Case Ground
5, 6
Output Common
7
Input Common
8
Case Ground
F
IGURE
3: P
IN
O
UT
DSCC NUMBER
DSCC D
RAWING
(5915)
96003-01HXC
FMSA
-461 F
ILTER
S
IMILAR
P
ART
FMSA-461/883
For exact specifications for a DSCC product, refer to the
DSCC drawing: http://www.dscc.dla.mil/programs/smcr
FMSA EMI FILTER
0.8 AMP
RL
Positive
Output
FMSA-461
Positive
Input
Input
Common
Case
Ground
Output
Common
C
R
DC/DC Converter
Input
Common
Case
Ground
Output
Common
RL
Multiple units
allowed up to
rated output current.
The RC output is an optional
damping circuit. It is recommended in
applications where 80 volt line
transients may occur with rise times
<200 s. See text page one
"Connection and Operation."
C = 10 F, 100V
C =
Sprague 109D106X9100C2
R = 2.2 , 5%, 1/4 W, Carbon comp.
Positive
Input
Positive
Output
F
IGURE
2: D
AMPING
C
IRCUIT
Typical Performance Curves: 25C Tc , nominal Vin, unless otherwise specified.
EMI I
NPUT
F
ILTERS
FMSA EMI FILTER
0.8 AMP
CE03 LIMIT
NARROWBAND
FREQUENCY (MHz)
EMISSION LEVEL (dB A)
0.1
1
10
50
90
80
70
60
50
40
30
20
10
0
.015
F
IGURE
4
FREQUENCY (MHz)
EMISSION LEVEL (dB A)
0.1
1
10
50
90
80
70
60
50
40
30
20
10
0
.015
NARROWBAND
CE03 LIMIT
F
IGURE
5
F
IGURE
6
MSA2805S converter without a filter.
MSA2805S converters at full load with
an FMSA-461 EMI filter
Typical Output Impedance (Z)
With Input Shorted
FMSA-461 EMI Filter
FREQUENCY (Hz)
MAGNITUDE OF Z
o
(Ohms)
10K
100K
1M
10.0
3.2
1.0
0.32
0.10
1K
2
F external capacitor on filter output
FMSA EMI Filter, Rev C, November 1, 2005 (format)
All technical information is believed to be accurate, but no responsibility is
assumed for errors or omissions. Interpoint reserves the right to make changes in
products or specifications without notice. MGH Series is a trademark of Interpoint
Corporation. Copyright 1994 - 2006 Interpoint Corporation. All rights reserved.
CASES
See cases A1 - A3
for pin configurations.
Dot on top of case
indicates pin one.
0.980 max
(24.89)
0.805 max
(20.45)
Materials
Header Cases A1 and A2
Kovar/Nickel/Gold
Case A3
Kovar/Nickel)
Cover
Kovar/Nickel
Pins
Kovar/Nickel/Gold,
matched glass seal
Case dimensions in inches (mm)
Tolerance 0.005
(0.13) for three decimal places
0.01
(0.3) for two decimal places
unless otherwise specified
CAUTION
Heat from reflow or wave soldering may damage the device.
Solder pins individually with heat application not exceeding 300C for 10 seconds per pin.
Case A maximum dimensions, Rev B, September 23, 2005
Please refer to the numerical dimensions for accuracy. All information is believed to be accurate,
but no responsibility is assumed for errors or omissions. Interpoint reserves the right to make
changes in products or specifications without notice.
Copyright 1999-2005 Interpoint Corp. All rights reserved.
CASE A MAXIMUM DIMENSIONS
BOTTOM VIEW
CASES
0.000
0.097
(2.46)
0.697
(17.70
Squared corner and dot on
top of case indicate pin one.
0.397
(10.08)
0.000
0.1
3
5 (
3
.4
3
)
0.
83
5 (21.21)
0.270 m
a
x
(6.9
8
)
0.000
0.7
3
5 (1
8
.67)
Projection Weld
Seam Seal
FMSA EMI Filter and STF EMI Filter
1
3
8
4
7
2
6 5
BOTTOM VIEW CASE A1
0.270 m
a
x
(6.
8
6)
0.000
0.27 0.02
(6.9 0.5)
0.27 0.02
(6.9 0.5)
0.018 0.002 dia.
(0.46 0.05)
Seal hole: 0.056 0.002 (1.42 0.05)
Case A1, Rev B, September 8, 2005
Please refer to the numerical dimensions for accuracy. All information is believed to be accurate,
but no responsibility is assumed for errors or omissions. Interpoint reserves the right to make
changes in products or specifications without notice.
Copyright 1999-2005 Interpoint Corp. All rights reserved.
Case dimensions in inches (mm)
Tolerance 0.005
(0.13) for three decimal places
0.01
(0.3) for two decimal places
unless otherwise specified
CAUTION
Heat from reflow or wave soldering may damage the device.
Solder pins individually with heat application not exceeding 300C for 10 seconds per pin
QUALITY ASSURANCE
Class H,
QML Screening
page 1 of 1
TEST 125C
125C
Class
H
STANDARD
/ES
/883
non-QML
non-QML
QML
Pre-cap Inspection
Method 2017, 2032
yes
yes
yes
Temperature Cycle (10 times)
Method 1010, Cond. C, -65C to 150C, ambient
no
no
yes
Method 1010, Cond. B, -55C to 125C, ambient
no
yes
no
Constant Acceleration
Method 2001, 3000 g
no
no
yes
Method 2001, 500g
no
yes
no
Burn-In
Method 1015, 160 hours at 125C case, typical
no
no
yes
96 hours at 125C case, typical
no
yes
no
Final Electrical Test MIL-PRF-38534, Group A
Subgroups 1 through 6: -55C, +25C, +125C case
no
no
yes
Subgroups 1 and 4: +25C case
yes
yes
no
Hermeticity Test
Fine Leak, Method 1014, Cond. A
no
yes
yes
Gross Leak, Method 1014, Cond. C
no
yes
yes
Gross Leak, Dip (1 x 10
-3
)
yes
no
no
Final Visual Inspection
Method 2009
yes
yes
yes
Test methods are referenced to MIL-STD-883 as determined by MIL-PRF-38534.
C
LASS
H, QML S
CREENING
QA Screening Class H, QML Rev B November 1, 2005 (typo).
This revision supercedes all previous releases. All technical infor-
mation is believed to be accurate, but no responsibility is
assumed for errors or omissions. Interpoint reserves the right to
make changes in products or specifications without notice.
Copyright 2005 Interpoint Corporation. All rights reserved.
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