FMGA SerieS™ eMi Filter

The Interpoint surface mount FMGA-461 EMI filter has been

designed to work with Interpoint surface mount MGA Series™

and MGH Series™ dc-dc converters. Multiple MGA or MGH

converters can be operated from a single FMGA filter provided

the total power line current does not exceed the filter’s maximum

current rating. The FMGA filter will reduce the converter’s power

line reflected ripple current to within the limit of MIL-STD-461C,

Method CE03 as shown in Figure 10 through Figure 14 on page

10. The filter uses only ceramic capacitors for reliable high-

temperature operation.

Where more than one pin has the same designation (e.g. pins

7, 8, and 9 are Positive Output), all of those pins must be

connected for output performance to meet the specifications.

The MGA Series has an internal 2 µF capacitor on its input

terminals and the MGH Series has an internal 0.47 µF capacitor

across its input power terminals. See Figure 3 on page 4.

When the MGA or MGH converters are used with the FMGA filter,

this capacitor becomes part of the filter and forms its final LC

output section. When 2 or 3 MGA or MGH converters are used

with a single filter, this capacitor becomes larger, improving the

rejection versus frequency.

The optional damping circuit shown in Figure 4 on page 4

will prevent filter overshoot caused by 80 volt transients with rise

times of less than 200 microseconds. The damping circuit can be

used with a 1.50 Ω resistor in series with the filter’s positive input

where the additional line loss can be tolerated. For transients

with rise times of greater than 200 microseconds, there is no

overshoot and the damping circuit is not required.

The FMGA EMI filter can be surface mounted with pick-and-

place equipment or manually. It is recommended that the case

be attached with flexible epoxy adhesive or silicone which is

thermally conductive (>1 watt /meter/°K).

Internal components are soldered with SN96 (melting

temperature 221°C) to prevent damage during reflow. Maximum

reflow temperature for surface mounting the FMGA filter is

220°C for a maximum of 30 seconds. SN60, 62, or 63 are the

recommended types of solder. Hand soldering should not exceed

300°C for 10 seconds per pin.

The hermetically sealed metal cases are available in two different

lead configurations. For case dimensions and options, see

Case B ,Figure 16 on page 12 and the solder pad layout of

Figure 17 on page 12.

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 Power Solutions

FMSA/FMGA eMi input Filters

28 VOlt iNput - 0.8 AMp

www.craneae.com/interpointcom

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FMSA/FMGA Rev AA - 2015.12.15