Crane Aerospace & Electronics Power Solutions
SMFLHP Single and Dual DC-DC Converters
28 Volt input – 100 Watt
Features
pꢀꢁꢀllꢂl ꢃꢄꢂꢁꢀꢅꢆꢃꢇ wꢆꢅh ꢈꢉꢁꢁꢂꢇꢅ ꢊhꢀꢁꢂ,
ꢉꢄ ꢅꢃ 3 ꢉꢇꢆꢅꢊ (ꢉꢄ ꢅꢃ 285 wꢀꢅꢅꢊ)
•ꢀ Operating temperature -55° to +125°C
•ꢀ Qualified to MIL-PRF-38534 Class H and K
•ꢀ Radiation hardness assurance (RHA) to level R 100 kRad(Si)
•ꢀ Input voltage range 19 to 40 VDC
•ꢀ Transient protection 80 V for 50 ms
•ꢀ Fully isolated, magnetic feedback
•ꢀ Fixed high frequency switching
•ꢀ Remote sense / output trim on single output models
•ꢀ Inhibit function
MODELS
•ꢀ Synchronization input and output
VDC Output
•ꢀ Indefinite short circuit protection
SINGLE
DUAL
±5
•ꢀ High power density with up to 87% efficiency
3.3
5
±12
±15
12
15
description
DeSign FeatureS
The Interpoint™ SMFLHP Series™ 28 volt dc-dc converters
are rated up to 100 watts output power over a -55°C to +125°C
temperature range with a 28 VDC nominal input. On dual output
models, up to 70% of the rated output power can be drawn from
either the positive or negative outputs. Current sharing allows
the units to be paralleled for total power of up to 285 watts. The
welded, hermetically sealed package is only 3.005 x 1.505 x
0.400 inches.
The SMFLHP Series converters are switching regulators that use
a quasi-square wave, single ended forward converter design with
a constant switching frequency of 600 kHz.
Isolation between input and output circuits is provided with a
transformer in the forward path and wide bandwidth magnetic
coupling in the feedback control loop. The SMFLHP Series
uses a unique dual loop feedback technique that controls output
current with an inner feedback loop and output voltage with a
cascaded voltage mode feedback loop.
Screening
SMFLHP converters offer screening options to Space Prototype
(O), Class H, or Class K. Radiation tolerant to Radiation
Hardness Assurance (RHA) levels of “-” (O), “P” or “R”, per
MIL-PRF-38534. Interpoint model numbers use an “O” in the
RHA designator position to indicate the “-” (dash) Radiation
Hardness Assurance level of MIL-PRF-38534, which is defined
as “no RHA”. See “Table 9: Element Evaluation” on page 14
and “Table 10: Environmental Screening and RHA Levels” on
page 15 for more information.
The additional secondary current mode feedback loop improves
transient response in a manner similar to primary current mode
control and allows for ease of paralleling.
Tight load regulation is achieved through a wide-bandwidth
magnetic feedback circuit. The output voltage on single SMFLHP
models can be easily trimmed up by adding an external resistor.
See “Figure 2: Sense Connections and Trim Table – Single
Output Models” on page 3 for voltage changes with different
resistor values.
Crane Aerospace & Electronics
Page 1 of 15
Power Solutions – Interpoint Products
10301 Willows Rd. NE, Redmond, WA 98052
+1 425.882.3100 • power@crane-eg.com
www.craneae.com/interpoint
Rev AA - 2013.08.31
The information in this document is a derivative of documents cleared by the Department
of Defense (DoD) Office of Security Review (OSR) for public release. OSR case numbers
09-S-1007 dated March 13, 2009 and 12-S-2048 dated MAY 29, 2012.