F
EATURES
• –55°C to +125°C operation
• Up to 50 dB attenuation
400 kHz to 50 MHz
• Transient suppression
• Compliant to
MIL-STD-461C, CE03
• Compatible with
MIL-STD-704E
DC power bus
EMI I
NPUT
F
ILTER
28 V
OLT
I
NPUT
FMC EMI FILTER
2.7 AMP
MODEL
FMC-461
FMC-461NT
2.7 Amp
2.7 Amp
Size (max): Non-flanged, case H1
2.125 x 1.125 x 0.400 (53.98 x 28.58 x 10.16 mm)
Flanged, case K2
2.910 x 1.125 x 0.400 inches (73.91 x 28.58 x 10.16 mm)
See Section B8, cases H1 and K2, for dimensions.
Weight:
48 grams maximum
Screening: Standard, ES, or 883 (Class H). See Section C2 for
screening options, see Section A5 for ordering information.
DESCRIPTION
The FMC-461™ EMI filter has been specifically designed to reduce
the input line reflected ripple current of Interpoint’s MHF, MTR, MTO,
MHV, MHF+, MHD, MTW, MHE, and MLP series of DC/DC
converters. It is intended for use in applications which have high
frequency switch-mode DC/DC converters and which must meet
MIL-STD-461C levels of conducted and radiated noise.
The FMC filter is built using thick-film hybrid technology and is
hermetically sealed in metal packages for military, aerospace, and
other high-reliability applications. The filter uses only ceramic
capacitors for reliable high temperature operation.
T
RANSIENT
S
UPPRESSION
The FMC-461 filter also features a fast-reacting (1 pico second)
transient suppressor which begins clamping the input voltage at
approximately 47 VDC, protecting the DC/DC converter from
damage from induced line transients.
O
PERATING
T
EMPERATURE
The filter is rated to operate with no degradation of performance
over the temperature range of -55°C to +125°C (as measured at the
baseplate). Above +125°C, current must be derated as specified on
the following page.
MIL-STD N
OISE
M
ANAGEMENT
When used in conjunction with Interpoint converters, the FMC-461
filter reduces input ripple current by 40 dB within the frequency band
of 200 kHz to 50 MHz. This gives the filter/converter combination a
performance which exceeds the CEO3 test of MIL-STD-461C.
Typical FMC-461 filter frequency response and output impedance
behavior are shown in Figures 4 and 5. CEO3 performance of a
typical converter with the FMC-461 filter connected is shown in
Figure 3.
I
NSERTION
L
OSS
The maximum DC insertion loss for the FMC-461 filter (at a load of
22 watts) represents a power loss of less than 2% at typical input
voltage.
L
AYOUT
R
EQUIREMENT
The case pin, and ideally the case, should be tied to the case of the
converter through a low-inductance connection.
B3-13
INTERPOINT [ INTERPOINT CORPORATION COMPANY ]
