B3-21

DESCRIPTION

Interpoint’s surface mount FMGA-461™ EMI filter has been

designed to work with Interpoint’s surface mount MGA and MGH

Series DC/DC converters. Multiple MGA or MGH Series converters

can be operated from a single FMGA filter provided the total power

line current does not exceed the filter’s maximum 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 Figures

4 through 7. 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 its input terminals

and the MGH Series has an internal 0.47 µF capacitor across its

input power terminals. 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 2 will prevent filter

overshoot caused by 80 V 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 tempera-

ture 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. See Section B8, case B.

The case of the filter must be connected to the case of the converter

through a low impedance connection to minimize EMI.

FMGA EMI FILTER

0.8 AMP

• –55°C to +125°C operation

• 50 dB min. attenuation at 500 kHz

differential mode

• 45 dB min. attenuation at 5MHz

common mode

• Compliant to MIL-STD-461C, CE03

• Compatible with MIL-STD-704A

through E

Size (max.): 1.010 x 0.880 x 0.250 inches (25.65 x 22.35 x 6.35 mm)

Shown with “Gull Wing” lead option, also available with straight

leads. See Section B8, case B, for dimensions and options.

Weight:

10.3 grams typical, 11.5 grams maximum

Screening:

Standard or ES. See Section C2 for screening options, see

Section A5 for ordering information.

MODEL

FMGA-461

0.8 amp