INTERPOINT STF28-461

EMI INPUT FILTER
28 VOLT INPUT
STF28-461
EMI FILTER
0.8 AMP
FEATURES
• Fully qualified to Class H or K
• Passive components for
maximum tolerance in space
environments
• –55° to +125°C operation
• 28 volt input
• Up to 0.8 amps throughput current
• 50 dB minimum attenuation
at 500 kHz
Size (max.):
• Compliant to MIL-STD-461C, CE03
Weight:
• Compatible with MIL-STD-704E
Screening:
DC power bus
MODEL
STF28-461
0.8 amp
0.975 x 0.800 x 0.270 (24.77 x 20.32 x 6.86 mm)
See Section B8, cases A1, for dimensions.
10.3 grams typical, 11.5 grams maximum
Standard, Class H, or Class K (MIL-PRF-38534)
See Section C2 for screening options, see
Section A5 for ordering information.
DESCRIPTION
The STF28-461™ EMI filter module has been designed as a
companion for Interpoint SMSA flyback power converters. Multiple
SMSA power converters can be operated from a single filter
provided the total power line current does not exceed the filter
maximum rating. The STF filter will reduce the SMSA’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 STF filter is fabricated using thick film hybrid technology and is
sealed in a metal package for space, military, aerospace and other
applications requiring EMI suppression.
SCREENING AND REPORTS
The STF28-461 filter offers three screening options – Standard,
Class H, or Class K. See Section C2, Quality Assurance, pages C27 through C2-9, for descriptions. Detailed reports on product
performance are also available and are listed on page C2-9.
OPERATION
The SMSA power converter has an internal capacitor across its
input power terminals. When the SMSA and STF filters are used
together, this capacitor becomes part of the filter and forms its final
LC output section.
The STF filter provides both differential and common mode rejection
bringing DC/DC converters into compliance with MIL-STD-461C
CE03. It is designed to be used with the SMSA, SMHF, and MCH
Series of converters. The STF filter can be used with multiple
converters up to the rated current of the filter.
For more information, contact your Interpoint representative
listed in Section A5.
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. STF28-461 is a trademark of Interpoint.
Copyright © 1999 Interpoint. All rights reserved.
B1-16
CASES
BOTTOM VIEW CASE A1
FMSA EMI Filter: Screening – Standard, ES, or 883
STF EMI Filter: Screening – Space Standard, H, or K
Projection Weld
Seam Seal
Squared corner and dot on
top of case indicate pin one.
0.697
(17.70
1
2 3
0.397
(10.08)
8
4
0.097
(2.46)
0.000
7
6 5
0.000
0.27 ±0.02
(6.9 ±0.5)
0.270 max
(6.98)
0.27 ±0.02
(6.9 ±0.5)
0.000
0.018 ± 0.002 dia.
(0.46 ± 0.05)
BOTTOM VIEW CASE A2
MCH Series: Screening – Standard, ES, or 883
SLH Series: Screening – Space Standard, H, or K
Seam Seal
Projection Weld
Squared corner and dot on
top of case indicate pin one.
0.697
(17.70
FIGURE 1: CASE A MAXIMUM DIMENSIONS
1 2
3
4
0.018 ± 0.002 dia.
(0.46 ± 0.05)
7
0.000
0.27 ±0.02
(6.9 ±0.5)
0.000
0.27 ±0.02
(6.9 ±0.5)
0.270 max
(6.98)
0.000
0.270 max
(6.86)
0.097
(2.46)
0.000
6
5
0.835 (21.21)
CAUTION
Heat from reflow or wave soldering may damage
the device. Solder pins individually with heat
application not exceeding 300°C for 10 seconds
per pin.
FIGURE 2: CASE A1
0.435 (11.05)
0.535 (13.59)
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
0.000
Materials
Header
Kovar/Nickel/Gold
(Case A3, Kovar/Nickel)
Cover
Kovar/Nickel
Pins
Kovar/Nickel/Gold,
matched glass seal
0.270 max
(6.86)
0.975 max
(24.77)
0.135 (3.43)
CASE A
BOTTOM VIEW
0.800 max
See Figures 2 - 4
(20.32)
for pin configurations.
0.735 (18.67)
0.835 (21.21)
Dot on top of case
indicates pin one.
0.135 (3.43)
0.235 (5.97)
CASE A
FIGURE 3: CASE A2
BOTTOM VIEW CASE A3
DCH Series: Screening – Standard or ES
Projection Weld
0.697
(17.70
1 2 3
8
16 15 14
9
0.835 (21.21)
Dot on top of case
indicates pin one.
0.135 (3.43)
0.235 (5.97)
0.335 (8.51)
Seam Seal
0.018 ± 0.002 dia.
(0.46 ± 0.05)
B8-6
0.000
0.27 ±0.02
(6.9 ±0.5)
0.000
0.350 max
(8.89)
0.000
0.27 ±0.02
(6.9 ±0.5)
Note: Although every effort has been made to render the case
drawings at actual size, variations in the printing process may
cause some distortion. Please refer to the numerical dimensions
for accuracy.
0.350 max
(8.89)
0.097
(2.46)
0.000
FIGURE 4: CASE A3
QA SCREENING
SPACE PRODUCTS
SPACE PRODUCTS
ELEMENT EVALUATION
TEST PERFORMED
(COMPONENT LEVEL)
STANDARD
CLASS
(O)
H
M/S
P M/S
P
CLASS
K
M/S
P
Element Electrical
yes
no
yes
yes yes
yes
Element Visual
no
no
yes
yes yes
yes
Internal Visual
no
no
yes
no
yes
no
Temperature Cycling
no
no
no
no
yes
yes
Constant Acceleration
no
no
no
no
yes
yes
Interim Electrical
no
no
no
no
yes
no
Burn-in
no
no
no
no
yes
no
Post Burn-in Electrical
no
no
no
no
yes
no
Steady State Life
no
no
no
no
yes
no
Voltage Conditioning /Aging
no
no
no
no
no
yes
Visual Inspection
no
no
no
no
no
yes
Final Electrical
no
no
yes
yes yes
yes
Wire Bond Evaluation*
no
no
yes
yes yes
yes
SEM
SLAM™/C-SAM:
Input capacitors only
(Add’l test, not req. by H or K)
no
no
no
no
yes
no
no
no
no
yes
no
yes
Notes
M/S
P
*
Active components (Microcircuit and Semiconductor Die)
Passive components
Not applicable to EMI filters that have no wirebonds
Definitions
Element Evaluation: Component testing/screening per MIL-STD-883 as determined by MIL-PRF-38534
SEM: Scanning Electron Microscopy
SLAM™: Scanning Laser Acoustic Microscopy
C-SAM: C - Mode Scanning Acoustic Microscopy
Applies to the following products:
SMFLHP Series
SMFL Series
SMHP Series (O&H only)
SMTR Series
SSP Series
SMHF Series
SMSA Series
SLH Series
SLIM Module
SFME120 EMI Filter
SFME28 EMI Filter
SFCS EMI Filter
SFMC EMI Filter
STF EMI Filter
C2-7
QA SCREENING
SPACE PRODUCTS
ENVIRONMENTAL SCREENING
TEST PERFORMED
(END ITEM LEVEL)
Non-destruct bond pull*
Method 2023
Pre-cap inspection
Method 2017, 2032
Temperature cycle
Method 1010, Cond. C
Constant acceleration
Method 2001, 3000 g
PIND Test
Method 2020, Cond. B
Radiography
Method 2012
Pre burn-in test
Burn-in, Method 1015, 125°C
96 hours
160 hours
2 x 160 hour (includes mid BI test)
Final electrical test
MIL-PRF-38534, Group A
Hermeticity test
Fine Leak,
Method 1014, Cond. A
Gross Leak,
Method 1014, Cond. C
Final visual inspection
Method 2009
STANDARD
(O)
CLASS
H
CLASS
K
no
no
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
no
no
yes
no
yes
no
yes
yes
yes
yes
no
no
no
yes
no
no
no
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
Test methods are referenced to MIL-STD-883 as determined by MIL-PRF-38534.
Note
* Not applicable to EMI filters that have no wirebonds.
Applies to the following products:
SMFLHP Series
SMFL Series
SMHP Series (O&H only)
SMTR Series
SSP Series
C2-8
SMHF Series
SMSA Series
SLH Series
SLIM Module
SFME120 EMI Filter
SFME28 EMI Filter
SFCS EMI Filter
SFMC EMI Filter
STF EMI Filter