• total ionizing dose (tid) guaranteed to 100 krad(si)
rHa level r, per MiL-std-883 method 1019
• single event effects (see) Let performance to
86 MeV cm
2
/mg
•
Qualified to MIL-PRF-38534 Class H and K
•
Transient protection 50 V for 50 ms
•
Fixed high frequency switching
•
Inhibit function
•
Synchronization input
•
Undervoltage lockout
MODeLS
OUTPUT VOLTAge (V)
SINgLe
3.3
5
5.2
12
15
DUAL
±5
±12
±15
•
Indefinite short circuit protection
The Interpoint
®
SMHF Series™ of 28 V dc-dc converters offers
a wide input voltage range of 16 to 45 volts and up to 15 watts of
output power. The units are capable of withstanding transients up
to 50 volts for up to 50 ms.
description
SMHF converters offer screening options up to Class K,
radiation hardness assurance (RHA) level “R”. See Table 10 on
page 15 for more information.
S
creening
The SMHF converter’s feed-forward compensation system
provides excellent dynamic response and noise rejection. Audio
rejection is typically 50 dB. Typical output voltage response for
a 50% to 100% step load transient is as low as 1.8% with a 150
µs recovery time, typical. See Table 5 on page 5 for more
information.
SMHF converters provide an inhibit terminal that can be used
to disable internal switching, resulting in no output and very
low quiescent input current. The converter is inhibited when the
inhibit pin is pulled low. The unit is enabled when the pin, which
is internally connected to a pull-up resistor, is left unconnected
or is connected to an open-collector gate. See Table 5 on page
5 for more information.
The SMHF Series’ synchronization feature allows the user to
match the switching frequency of the converter to the frequency
of the system clock. This allows the user to adjust the nominal
550 kHz operating frequency to any frequency within the range of
500 kHz to 600 kHz by applying a compatible input of the desired
frequency to pin 5.
SMHF Series converters provide short circuit protection by
restricting the output current to approximately 140% of the
full load output current. The output current is sensed in the
secondary stage to provide highly predictable and accurate
current limiting, and to eliminate foldback characteristics.
Undervoltage lockout prevents the units from operating below
approximately 14 volts input to keep system current levels
smooth, especially during initialization or re-start operations.
c
onverter
D
eSign
The SMHF converters are switching regulators that use a
quasi-square wave, single-ended forward converter design with
a constant switching frequency of 550 kHz typical. Isolation
between input and output circuits is provided with a transformer
in the forward path and a temperature compensated opto-coupler
in the feedback control loop. The opto-coupler is radiation
tolerant and is especially selected for space applications.
Dual output models maintain cross regulation with tightly
coupled output magnetics. Up to 70% of the total output power
is available from either output, providing the opposite output
is simultaneously carrying 30% of the total output power.
Predictable current limit is accomplished by directly monitoring
the output load current and providing a constant current output
above the overload point.
Crane Aerospace & Electronics
Power Solutions - Interpoint Products
10301 Willows Road NE, Redmond, WA 98052
+1.425.882.3100 • power@crane-eg.com
www.craneae.com/interpoint
SMHF Rev AD - 2014.08.14
The information in this document has been cleared by the Department of Defense (DoD)
Office of Security Review (OSR) for public release. OSR case numbers 12-S-2814 dated
August 28, 2012 and 12-S-2048 dated May 29, 2012.
Page 1 of 15
Crane Aerospace & Electronics Power Solutions
sMHF single and dual dc-dc converters
16-45 VoLt input – 15 Watt
5
μH
Regulator
Positive
Input
2
μF
Positive
Output
I
D
Inhibit
PWM
Controller
I
C
Input
Common
Output
Common
FET
Driver
Limit
Ref.
F
igure
1: SMHF S
ingle
o
utput
, B
lock
D
iagraM
Positive
Input
5
μH
Regulator
L2A
2
μF
Positive
Output
I
D
Inhibit
PWM
Controller
I
C
Input
Common
FET
Driver
R
S
Limit
Ref.
R
S
L2B
Output
Common
Negative
Output
F
igure
2: SMHF D
ual
o
utput
, B
lock
D
iagraM
www.craneae.com/interpoint
SMHF Rev AD - 2014.08.14
Page 2 of 15
Crane Aerospace & Electronics Power Solutions
sMHF single and dual dc-dc converters
16-45 VoLt input – 15 Watt
pin out
pin
1
2
3
4
5
6
7
8
single output
Inhibit
No connection
dual output
Inhibit
Positive Output
Output Common
Negative Output
Sync
Case ground
Input Common
Positive Input
Output Common
Positive Output
Sync
Case ground
Input Common
Positive Input
t
aBle
1: p
in
o
ut
Dot on top of cover
indicates pin one.
BOTTOM VIEW
SMHF SINGLE AND DUAL
NON-FLANGED OR FLANGED
8
7
6
1
2
3
4
5
Dotted line outlines flanged package option.
See Figure 27 on page 12 and Figure 28 on page 13
for dimensions.
F
igure
3: p
in
o
ut
Inhibit (pin 1)
Sync (pin 5)
pins not in use
Leave unconnected
Connect to Input Common (pin 7)
t
aBle
2: p
inS
n
ot in
u
Se
www.craneae.com/interpoint
SMHF Rev AD - 2014.08.14
Page 3 of 15
Crane Aerospace & Electronics Power Solutions
sMHF single and dual dc-dc converters
16-45 VoLt input – 15 Watt
ModeL nuMbering key
Base Model
Input Voltage
SMHF
28 05 S F / K
R
S
tandard
M
icrocircuit
d
rawing
(SMd)
5962R0251002KXC
5962R9213902KXC
5962R9166402KXC
5962R9160102KXC
5962R9555902KXC
5962R9214402KXC
5962R9161402KXC
sMd nuMbers
SMHF S
iMilar
P
art
SMHF283R3S/KR
SMHF2805S/KR
SMHF2812S/KR
SMHF2815S/KR
SMHF2805D/KR
SMHF2812D/KR
SMHF2815D/KR
Output Voltage
Number of Outputs
(S = single, D = dual)
Case Option
(Non-flanged case has no designator
in this position)
Environmental Screening
Radiation Hardness
Assurance (RHA)
F
igure
4: M
oDel
n
uMBering
k
ey
To indicate the flanged case option change the “X” to
“Z” In the SMD number. The SMD number shown is for
Class K screening, non-flanged, and radiation hardness
assurance (RHA) level R. See the SMD for the numbers
for other screening and radiation levels. For exact speci-
fications for an SMD product, refer to the SMD drawing.
SMDs can be downloaded from: http://www.landandmari-
time.dla.mil/programs/smcr/
t
aBle
3: SMD n
uMBer
c
roSS
r
eFerence
t
o deterMine tHe Model nuMber enter one oPtion FroM eacH category in tHe ForM below
.
category
options
FiLL in For
ModeL #
base Model and
input Voltage
output Voltage
2
3R3, 05, 5R2, 12, 15
sMHF28
05, 12, 15
number of
outputs
3
S
D
case option
4
(non-flanged, leave blank)
F (flanged)
screening
5
O
H
K
sMHF28
__________
rHa
6
O
P
R
ModeL nuMber options
1
Notes:
1. See Model Numbering Key above for an example of a model number.
2. Output Voltage: An R indicates a decimal point. 3R3 is 3.3 volts out. The values of 3.3 and 5.2 are only available in single output models.
3. Number of Outputs: S is a single output and D is a dual output
4. Case Options: For the standard case (Figure 27 on page 12) leave the Case Option blank. For the flanged case option (Figure 28 on page 13), insert the letter F
in the Case Option position.
5. Screening: A screening level of O is a space prototype and is only available with RHA O. See Table 9 on page 14 and Table 10 on page 15 for more information.
6. RHA: 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.” RHA O is only available with screening level O. See Table 10 on page 15 for more information.
/
_______
t
aBle
4: M
oDel
n
uMBer
o
ptionS
www.craneae.com/interpoint
SMHF Rev AD - 2014.08.14
Page 4 of 15
Crane Aerospace & Electronics Power Solutions
sMHF single and dual dc-dc converters
16-45 VoLt input – 15 Watt
t
aBle
5: o
perating
c
onDitionS
- a
ll
M
oDelS
, 25°c
caSe
, 28 v
in
,
unleSS otHerwiSe SpeciFieD
SMHF SeRIeS
PARAMeTeR
LeAD SOLDeRINg TeMPeRATURe
1
STORAge TeMPeRATURe
1
CASe OPeRATINg
TeMPeRATURe
DeRATINg OUTPUT POWeR/CURReNT
1
eSD RATINg
1
MIL-PRF-38534, 3.9.5.8.2
ISOLATION: INPUT TO OUTPUT OR ANY
PIN TO CASe eXCePT CASe PIN
INPUT TO OUTPUT CAPACITANCe
1
UNDeRVOLTAge LOCKOUT
1
CURReNT LIMIT
1, 2
AUDIO ReJeCTION
1
CONVeRSION FReQUeNCY
SYNCHRONIZATION
FRee RUN
-55°C TO +125°C
INPUT FReQUeNCY
DUTY CYCLe
1
ACTIVe LOW
ACTIVe HIgH
1
ReFeReNCeD TO
IF NOT USeD
INHIBIT ACTIVe LOW (OUTPUT DISABLeD)
Do not apply a voltage to the inhibit pin
INHIBIT PIN PULLeD LOW
INHIBIT PIN SOURCe
CURReNT
1
ReFeReNCeD TO
INHIBIT ACTIVe HIgH (OUTPUT eNABLeD)
Do not apply a voltage to the inhibit pin
INHIBIT PIN CONDITION
OPeN INHIBIT PIN
VOLTAge
1
7.5
—
—
V
IN
% OF FULL LOAD
FULL POWeR
ABSOLUTe
1
LINeARLY
MIL-STD-883 MeTHOD 3015
CLASS 1C
@ 500 VDC AT 25°C
100
—
—
—
—
480
500
40
—
4.5
CONDITIONS
10 SeCONDS MAX.
—
-65
-55
-55
ALL MODeLS
MIN
TYP
—
—
—
—
MAX
300
+150
+125
+135
UNITS
°C
°C
°C
From 100% at 125°C to 0% at 135°C
1000-1999
—
60
14
140
50
550
—
—
—
—
—
—
—
—
—
620
600
60
0.8
5.0
V
Megohms
pF
V
%
dB
kHz
kHz
%
V
INPUT COMMON
CONNeCT TO INPUT COMMON
—
—
0.8
5
V
mA
INPUT COMMON
OPeN COLLeCTOR OR
UNCONNeCTeD
—
12
V
For mean time between failures (MTBF) contact Applications Engineering
powerapps@crane-eg.com +1.425.882.3100 option 7
Notes:
1. guaranteed by qualification test and/or analysis. Not an in-line test.
2. Dual outputs: The over-current limit will trigger when the sum of the currents from both outputs reaches 140% (typical value) of the
