FEATURES
Built in MIL-STD-461 EMI filter
Output trim from 51% to 124% of nominal
Operating temperature -55° to +125°C•
Qualified to MIL-PRF-38534 Class H and K•
Radiation hardness assurance (RHA) to •
level F 300 kRad(Si)
Input voltage range 19 to 56 VDC •
Transient protection 80 V for 120 ms•
Fully isolated, 5 port isolation•
Dual magnetic feedback•
Fixed high frequency switching•
Remote sense•
Inhibit function•
Synchronization input•
Indefinite short circuit protection•
Radiation tolerant to •
1 x 10 - 12 protons/cm2 neutron or proton fluence
10 - 11 rad(Si)/sec dose rate
3 x 10 - 5 rad(Si) total dose
SEE - LET to 80 MeV cm - 2/mg
Meets MIL-STD-704A transient standards•
DESCRIPTION
The SMRT28 Series™ of DC/DC converters offers up to 35
watts of power in a radiation tolerant design. The low profile
SMRT28 converters are manufactured in Interpoint’s fully
certified and qualified MIL-PRF-38534 production facility and
packaged in hermetically sealed steel cases. They are ideal for
use in programs requiring high reliability, small size, and high
levels of radiation hardening assurance.
The SMRT28 converters are switching regulators which use a
two-phase, phase shifted flyback design with a nominal switching
frequency of 300 kHz. Close regulation is maintained with
advanced constant frequency pulse width modulation design
techniques. The SMRT28’s feed-forward compensation and
discontinuous topologies provide high levels (80 dB peak) of
input-to-output ripple rejection.
Two independent feedback loops are used to regulate the dual
and triple outputs, one feedback loop regulates the two-phased
single output. Each set of outputs is electrically isolated from the
other and from the input. This product configuration eliminates
cross regulation effects between output sets.
Configurations:
•SingleOutput:Onetwo-phasesingleoutput
•DualOutput:Twosingle-phasesingleoutputs
•TripleOutput:Onesingle-phaseindependent
Main output and one single-phase dual output.
(± Auxiliary output)
MODELS
VDC Ou t p u t
SINGLE
3.3
5
8.7
12
15
DUAL
±5
±12
±15
TRIPLE
+3.3 & ±12
+3.3 & ±15
+5 & ±7
+5 & ±12
+5 & ±15
Cleared by the U.S. Department of Defense (DoD) Office of Security Review (OSR)
for public release. OSR case number 11-S-0729, dated January 4, 2011.
Crane Aerospace & Electronics Power Solutions
SMRT28 Single, Dual and Triple Space DC/DC Converters
Page 1 of 22
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Crane Aerospace & Electronics
Crane Electronics, Inc.
Power Solutions Interpoint
POBox97005•RedmondWA98073-9705
425.882.3100•power@crane-eg.com
www.craneae.com/interpoint
un D e r V O l t a g e lO C k O u t
The converters have an undervoltage lockout that will allow
power conversion at approximately 17 volts on a rising input
voltage and a conversion shut-down on a falling voltage at
approximately 14.5 volts.
In h I b I t Fu n C t I O n
The SMRT28 Series incorporates an inhibit terminal that can
be used to disable internal switching. It is not recommended
to tie the Inhibit pin of an SMRT28 directly to the Inhibit pin of
another converter as the SMRT28 Inhibit pin can sink current.
Whenpullingmultipleinhibitsignalslowaseparateinterface
is recommended for each SMRT28. The converter is inhibited
when the inhibit pin is pulled low (0.4 V). In the inhibit mode the
inhibit pin current requirement is less than ~2 mA. The converter
resumesnormaloperationwhenahigh(≥2.4V)signaloropen
circuit is applied to the inhibit pin. The open circuit voltage of
the inhibit is 5 to 6 volts. Although open circuit is the preferred
method for the enabled state, up to 10 volts may be applied to
the inhibit pin.
Sy n C h r O n I z a t I O n
The Sync Input is isolated which allows Sync Return to be tied to
the primary side, secondary side, or float with respect to all inputs
and outputs. Input current into this pin is limited by a series 1 k
ohm resistance.
Ou t p u t VO l t a g e tr I m
The output voltage of each set can be trimmed from 51% to
125% of nominal (varies by model, see trim instructions on page
4). The following are “sets” of voltages in relation to trim:
•Tripleoutputmodels:Mainoutputisoneset,thedualoutputs
are another set.
•Dualoutputs:Eachoutputisa“set.”
One set can be trimmed using the trim pin, the other set can
be trimmed (up only) using the positive sense pin.
•Single:Oneset
ra D I a t I O n tO l e r a n C e
The SMRT28 DC/DC converters are designed to provide
continuous normal operation through radiation levels associated
with space missions and in tactical and strategic military
environments. The converters will operate normally in radiation
environments with up to 1 x 1012 neutrons per square centimeter
neutron fluence, 1011 rad(Si) per second dose rate, and 3x105
rad(Si) total dose.
These levels of radiation tolerance make the SMRT28 converters
suitable for electronics in programs where operation in high
radiation environments is required.
At the highest dose rate (1011 rad(Si)/sec dose rate) there will be
an upset resulting in a dip in the voltage. This is non-destructive
to the unit. The converter will operate through the upset.
SC r e e n I n g
SMRT28 converters offer the following screening options:
Space Prototype (O), Class H, or Class K. Radiation tolerant to
Radiation Hardness Assurance (RHA) levels of “-” (O), “P”, “R” or
“F”, 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 Screening Tables 1, 2 and 3 for more information.
emI
The SMRT28 has a built-in EMI input filter which brings the
conducted emissions into compliance with both methods of
MIL-STD-461, revisions C-CE03 and D-/E-/F-CE102.
Se n S e
Tight load regulation is maintained via wide bandwidth magnetic
feedback and through the use of remote sense on single output
models and one output (Output “A”) of the dual units. The sense
feature can be used to adjust the output voltage by connecting a
resistor between the positive sense line and the positive output.
Se n S e Ad j u S t In S t r u c t I o n S f o r
ou t p u t A o n du A l Mo d e l S
Ad j u S t up on l y
(See trim tables on page 4 for more options)
RaD j u S t = 240 ( Vout - Vnom )
Vmax - Vout
Vout = desired output voltage
Vnom = nominal unadjusted output voltage
Vmax = maximum achievable output voltage
5V Vmax = 6.0 V
12V Vmax = 14.68 V
15V Vmax = 18.36V
Note: RADJUST should be connected
between Sense A (pin 8) and Vout A (pin 11).
Crane Aerospace & Electronics Power Solutions
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Operating COnditiOns and CharaCteristiCs
Input Voltage Range
19 to 56 VDC continuous•
80 V for 120 ms transient•
Output Power
Up to 35 watts depending on model•
Lead Soldering Temperature (10 sec per pin)
300°C•
Storage Temperature Range (Case)
-65°C to +150°C•
Case Operating Temperature (Tc)
-55°C to +125°C full power•
-55°C to +135°C absolute•
Derating Output Power/Current
Linearly from 100% at 125°C to 0% at 135°C•
Power Dissipation (Pd)
20to31W•
Output Voltage Temperature Coefficient
100 ppm/°C max•
Current Limit
125% of full load typical•
Isolation at 25°C
100 megohm minimum at 500 V•
Audio Rejection
50 dB typical•
Conversion Frequency
300 kHz typ 270 kHz min, 330 kHz max•
Radiation (will operate through)
1x10• 12 neutrons/cm2 neutron or proton fluence
Radiation dose rate 10• 11 rad(Si) /sec
Total dose up to 300 kRad(Si) •
• SEE - LET to 80 MeV cm2/mg
meChaniCal and envirOnmental
Size (maximum)
2.705 x 2.205 x 0.400 inches (68.71 x 56.01 x 10.16 mm)•
See case S for dimensions.
Weight (maximum)
100 grams maximum•
Screening
Space Prototype, Class H, or Class K are radiation tolerant
to Radiation Hardness Assurance (RHA) levels of “-” (O), “P”,
“R”, or “F” 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 Screening Tables 1, 2 and 3 for more information. Available
configurations: OO, HP, HR, KP, KR, KF
synC and inhibit
Sync
Input frequency 270-330 kHz•
Duty cycle 20% min, 80% max •
2.5 V p-p minimum amplitude•
10 V p-p maximum amplitude•
Sync circuit is floating and isolated•
If sync is used at lower end of the range, full load •
operation is not guaranteed.
Inhibit
Converter disabled (active low)•
INH referenced to input common
Active low, pulled to 0.4 V or lower
Inhibit pin current < 2 mA
Converter enabled (active high)•
Active high >2.4 V
Not to exceed 10 V
Open pin voltage 5 to 6 V
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
TRIM TABLES
tr I m D O w n
Singles
Rt r I m should be connected between the Trim pin and Positive Sense pin.
Duals
Rt r I m should be connected between the Trim B pin and Positive Vout B
pin. This only trims output B, output A can use the sense pin to trim up
only. See page 2 for instructions on trimming up output A.
Triples
Rt r I m should be connected between the Trim A pin and Positive Vout
A pin to adjust the Main output.
Rt r I m should be connected between the Trim B pin and Positive Vout
B pin to adjust the Auxiliary outputs.
Rt r I m = K ( Vout - Vmin )
Vnom - Vout
Vout = Desired Voltage; K/Vmin/Vnom from table below.
VNOM K VMIN % OF VNOM
3.3 3500 3.18 96
5.0 4520 4.16 83
7.0 8020 5.47 78
8.7 9040 6.13 70
12 11030 7.05 58
15 12900 7.65 51
1
2
3
4
5
14
13
12
11
10
9
8
SMRT Single
Sense
Trim
1
2
3
4
5
14
13
12
11
10
9
8
SMRT Dual
Vout B
Trim B
1
2
3
4
5
14
13
12
11
10
9
8
SMRT Triple
Vout A
Trim A
Trim B
+Vout B
tr I m up
Singles
Rt r I m should be connected between the Trim pin and Sense Return pin.
Duals
Rt r I m should be connected between the Trim B pin and Vout B Return pin.
This only trims output B, output A can use the sense pin to trim up only.
Triples
Rt r I m should be connected between the Trim A pin and Vout A Return pin
to adjust the Main outputs.
Rt r I m should be connected between the Trim B pin and Vout B Return pin
to adjust the Auxiliary outputs.
Rt r I m = K ( Vmax - Vout )
Vout - Vnom
Vout = Desired Voltage; K/Vmax/Vnom from table below.
VNOM K VMAX % OF VNOM
3.3 3000 3.70 112
5.0 3000 6.26 125
7.0 5300 8.27 118
8.7 5300 10.46 149
12 5300 14.69 122
15 5300 18.54 124
1
2
3
4
5
14
13
12
11
10
9
8
SMRT Single
Sense Return
Trim
1
2
3
4
5
14
13
12
11
10
9
8
SMRT Dual
Vout B Return
Trim B
1
2
3
4
5
14
13
12
11
10
9
8
SMRT Triple
Vout A Return
Trim A
Trim B
Vout B Return
FI g u r e 1: tr I m DO w n DI a g r a m S FI g u r e 2: tr I m up DI a g r a m S
Note: Do not exceed maximum power rating when trimming up.
Note: Do not exceed maximum current rating when trimming down,
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
FI g u r e 3: Smrt SI n g l e bl O C k DI a g r a m
Bias 1
Error Amp / ref /
compensation
Bias 1
EMI Filter
PWM
Isolation
PWM
Isolation
28V
28V
Vout A Rtn.
OCP
OCP
Inhibit
Vin
Vin Rtn.
Trim
Sense
Sense Rtn.
Vout A
Vout A
Vout A Rtn.
Clock
Phase A
Phase B
Sync In
Bias 2
Oscillator
Oscillator
Bias 1
Bias 2
Feed forward
compensation
28V
Feedback
Feedback
5.1V Z
Prim. Bias
Primary
Secondary
Sync Rtn.
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
FI g u r e 4: Smrt Du a l bl O C k DI a g r a m
Bias 1
Error Amp / ref /
compensation
Bias 1
EMI Filter
Prim. Bias
PWM
Isolation
PWM
Isolation
28V
28V
Vout A Rtn.
Vout A Rtn
OCP
OCP
Inhibit
Vin
Vin Rtn.
Sense A
Sense A Rtn.
Vout A
Vout B
Vout B Rtn.
Vout B Rtn.
Clock
Phase A
Phase B
Prim. Bias
Prim. Bias
Sync In
Prim. Bias
Bias 2
Oscillator
Bias 1
Bias 2
Feed forward
compensation
28V
Prim. Bias
Feedback
Feedback
5.1V Z
Prim. Bias
Primary
Secondary
Sync Rtn.
Oscillator
Bias 2
Trim B
Error Amp / ref /
compensation
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
FI g u r e 5: Smrt tr I p l e bl O C k DI a g r a m
Vout B Neg.
Bias 1
Error Amp / ref /
compensation
Bias 1
EMI Filter
Prim. Bias
PWM
Isolation
PWM
Isolation
28V
28V
Vout A Rtn.
Vout A Rtn.
OCP
OCP
Inhibit
Vin
Vin Rtn.
Trim A
Vout A
Vout B Pos.
Vout B Rtn.
Vout B Rtn.
Clock
Phase A
Phase B
Prim. Bias
Prim. Bias
Sync In
Prim. Bias
Bias 2
Oscillator
Bias 1
Bias 2
Feed forward
compensation
28V
Feedback
Feedback
5.1V Z
Prim. Bias
Primary
Secondary
Sync Rtn.
Oscillator
Bias 2
Trim B
Error Amp / ref /
compensation
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
FI g u r e 6: pIn Ou t
1
2
3
4
5
14
13
12
11
10
9
8
TOP VIEW
See case S for dimensions.
PIN OUT
Pin Single Output Dual Output Triple Output
1 Vin Vin Vin
2 Vin Return Vin Return Vin Return
3 Inhibit Inhibit Inhibit
4 Sync In Sync In Sync In
5 Sync Return Sync Return Sync Return
8 Sense Sense A Trim B
9 Sense Return Sense A Return Vout B Negative
10 Vout A Return 1Vout A Return Vout B Return
11 Vout A 1Vout A Vout B Positive
12 Trim Trim B Trim A
13 Vout A 1Vout B Vout A
14 Vout A Return 1Vout B Return Vout A Return
1. To meet specifications for Single Output models, Vout A pins (11 and 13) must be tied together and Vout A
Return pins (10 and 14) must be tied together.
PINS NOT IN USE
Inhibit: single, dual and triple Leave unconnected
Sync In Connect to Sync Return
Sense Lines Must be connected to appropriate outputs
Trim (all) Leave unconnected
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
MODEL NUMBERING KEY
SMRT 28 515 T / K F
Base Model
Input Voltage
Output Voltage
Screening
Radiation Hardness
Assurance (RHA)
Number of Outputs
(S=single, D=dual, T=triple)
(single or dual Vout for single or dual models
main and aux. Vout for triple models)
SMD NUMBERS
St A n d A r d MI c r o c I r c u I t
dr A w I n g (SMd)
SMrt28 SIMIlAr pA r t
5962F0622001KXC SMRT283R3S/KF
5962F0622101KXC SMRT2805S/KF
5962F0821001KXC SMRT2812S/KF
5962F0622201KXC SMRT2815S/KF
5962F0622301KXC SMRT2805D/KF
5962F0720201KXC SMRT2812D/KF
5962F0622401KXC SMRT2815D/KF
5962F0821101KXC SMRT283R312T/KF
5962F0821201KXC SMRT283R315T/KF
5962F0622501KXC SMRT28512T/KF
5962F0622601KXC SMRT28515T/KF
The SMD number shown is for Class K screening and
Radiation Hardness Assurance (RHA) level F. See the
SMD for the numbers for other screening and radiation
levels. For exact specifications for an SMD product, refer
to the SMD drawing. SMDs can be downloaded from:
http://www.dscc.dla.mil/programs/smcr
MODEL SELECTION
on t h e l I n e S b e l o w , e n t e r o n e S e l e c t I o n f r o M e A c h c A t e g o r y t o d e t e r M I n e t h e M o d e l n u M b e r .
CATEGORY
SMRT28
/ _______
Base Model and
Input Voltage
Output Voltage 1Number of Outputs 2 Screening 3RHA 4
SELECTION SMRT28 is the only
available selection
3R3, 05, 8R7, 12, 15 S O O
05, 12, 15 D H P
3R312, 3R315, T K R
507, 512, 515 F
Notes:
1. Output Voltage: An R indicates a decimal point. 3R3 is 3.3 volts out. The 3R3 output voltage is only available in single and triple output models. The 3R312
and 3R315 triple output converters are +3.3 volt main and ±12 or ±15 volt auxiliaries. 512 and 515 triple output converters are +5 volt main and ±12 or ±15 volt
auxiliaries.
2. Number of Outputs: S is a single output, D is a dual output, and T is a triple output
3. Screening: A screening level of O is a Space Prototype and is only used with RHA O. See Screening Tables 2 and 3 for more information.
4. 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 Screening Table 3 for more information.
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
Notes
1. Guaranteed by design, not tested.
2. To maintain tight regulation over the full input voltage range a minimum load of 2% of full load should be used on all outputs.
3. Converters meet MIL-STD-461 specification revisions for conducted emissions C-CE03 and D-/E-/F-CE-102. The actual value of input ripple current is much less, the
limit in the characteristic table is based on measurement resolution..
4. Maximum power dissipation when output is shorted.
5. Recovery time is measured from application of the transient to point at which VOUT is within 1% of VOUT at final value.
6. Transition time >10 µs.
7. Half load to/from full load.
8. Measured from release of inhibit or input voltage step
SINGLE OUTPUT MODELS SMRT283R3S SMRT2805S SMRT288R7S
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX MIN TYP MAX
Output VOltage 3.23 3.30 3.37 4.90 5.00 5.10 8.52 8.70 8.87 VDC
Output Current 20 6.97 0 6.0 0 4.0 A
Output pOwer 2VIn = 19 t O 56 VDC 0 23 0 30 0 35 W
Output rIpple 10 khz - 20 mhz 280 200 200 mV p-p
lIne regulatIOn 2VIn = 19, 50 VDC 5 30 5 30 5 30 mV
lOaD regulatIOn 5 40 5 40 5 80 mV
VIn = 19, 50 90 70 80
tOtal regulatIOn 1
VOut
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
3.0 3.6 4.7 5.3 8.3 9.1 VDC
Input VOltage COntInuOuS 19 28 56 19 28 56 19 28 56 VDC
tranSIent 1 120 ms 0 80 0 80 0 80 V
Input Current InhIbIteD 50 50 50
mA
nO lOaD 110 110 115
Input rIpple Current 310 kHz - 20 MHz 10 50 10 50 10 50 mA p-p
eFFICIenCy 60 66 72 %
lOaD Fault 4, 5 POWERDISSIPATION 31 28 25 W
reCOVery 1 25 25 25 ms
Step lOaD reSpOnSe 5, 6, 7 tranSIent ±450 ±450 ±450 mV pk
reCOVery 3 3 4 ms
Step lIne reSpOnSe 1, 5, 6 19 - 50 - 19 VIn
tranSIent ±500 ±500 ±500 mV pk
reCOVery 4 4 4 ms
Start-up 8 Delay
nO lOaD anD Full 35 25 60 ms
OVerShOOt 50 50 95 mV pk
CapaCItIVe lOaD 1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 5000 5000 µF
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
SINGLE OUTPUT MODELS SMRT2812S SMRT2815S
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX
Output VOltage 11.76 12.00 12.24 14.70 15.00 15.30 VDC
Output Current 2 2.92 2.33 A
Output pOwer 2VIn = 19 t O 56 VDC 0 35 0 35 W
Output rIpple 10 khz - 20 mhz 200 180 mV p-p
lIne regulatIOn 2VIn = 19, 50 VDC 5 30 5 30 mV
lOaD regulatIOn 5 40 5 40 mV
VIn = 19, 50 VDC 90 90
tOtal regulatIOn 1
VOUT
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
10.9 13.1 14.0 16.0 VDC
Input VOltage COntInuOuS 19 28 56 19 28 56 VDC
tranSIent 1 120 ms 0 80 0 80 V
Input Current InhIbIteD 50 50 mA
nO lOaD 110 110
Input rIpple Current 310 kHz - 20 MHz 10 50 10 50 mA p-p
eFFICIenCy 75 75 %
lOaD Fault 4, 5 POWERDISSIPATION 20 20 W
reCOVery 1 25 25 ms
Step lOaD reSpOnSe 5, 6, 7 tranSIent ±575 ±575 mV pk
reCOVery 3 3 ms
Step lIne reSpOnSe 1, 5, 6 19 - 50 - 19 VIn
tranSIent ±700 ±700 mV pk
reCOVery 4 4 ms
Start-up 8 Delay
nO lOaD anD Full 25 25 ms
OVerShOOt 120 150 mV pk
CapaCItIVe lOaD 1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 5000 µF
Notes
1. Guaranteed by design, not tested.
2. To maintain tight regulation over the full input voltage range a minimum load of 2% of full load should be used on all outputs.
3. Converters meet MIL-STD-461 specification revisions for conducted emissions C-CE03 and D-/E-/F-CE-102. The actual value of input ripple
current is much less, the limit in the characteristic table is based on measurement resolution..
4. Maximum power dissipation when output is shorted.
5. Recovery time is measured from application of the transient to point at which VOUT is within 1% of VOUT at final value.
6. Transition time >10 µs.
7. Half load to/from full load.
8. Measured from release of inhibit or input voltage step
Crane Aerospace & Electronics Power Solutions
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
DUAL OUTPUT MODELS SMRT2805D SMRT2812D SMRT2815D
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX MIN TYP MAX
Output VOltage VO u t a 4.90 5.00 5.10 11.76 12.00 12.24 14.70 15.00 15.30 VDC
VO u t b 4.90 5.00 5.10 11.76 12.00 12.24 14.70 15.00 15.30
Output Current 2, 3 VO u t a 3.0 1.46 1.17
VO u t b 3.0 1.46 1.17 A
Output pOwer 2, 3
VIn = 19 t O 56 VDC
VO u t a 0 15 0 17.5 0 17.5 W
VO u t b 0 15 0 17.5 0 17.5
Output rIpple 10 khz - 20 mhz 200 200 180 mV p-p
lIne regulatIOn 2VIN = 19, 50 VDC 30 5 25 5 30 mV
lOaD regulatIOn 5 40 5 50 5 40 mV
VIN = 19, 50 VDC 70 100 70
tOtal regulatIOn 1
VOUT
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
±4.6 ±5.4 ±10.9 ±13.1 ±14.0 ±16.0 VDC
Input VOltage 4COntInuOuS 19 28 56 19 28 56 19 28 56 VDC
tranSIent 120 ms 0 80 0 80 0 80 V
Input Current InhIbIteD 4 50 50 50 mA
nO lOaD 110 110 110
Input rIpple
Current 410 kHz - 20 MHz 10 50 10 150 10 50 mA p-p
eFFICIenCy 66 75 75 %
lOaD Fault 5, 6 pOwer DISSIpatIOn 28 20 20 W
reCOVery 1 25 25 25 ms
Step lOaD
reSpOnSe 6, 7, 8
tranSIent ±450 ±450 ±575 mV pk
reCOVery 3 2 3 ms
Step lIne
reSpOnSe 1, 6, 7
19 - 50 - 19 VIN
tranSIent ±500 ±1000 ±700 mv pk
reCOVery 4 3 4 ms
Start-up 9Delay
nO lOaD anD Full 25 20 25 ms
OVerShOOt 50 350 150 mV pk
CapaCItIVe lOaD1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 5000 5000 µF
Notes
1. Guaranteed by design, not tested.
2. The specified maximum current/power is available from each output.
3. To maintain tight regulation over the full input voltage range a minimum load of 2% of full load should be used on all outputs.
4. Converters meet MIL-STD-461 specification revisions for conducted emissions C-CE03 and D-/E-/F-CE-102. The actual value of input ripple current is much less, the
limit in the characteristic table is based on measurement resolution..
5. Maximum power dissipation when output is shorted.
6. Recovery time is measured from application of the transient to point at which VOUT is within 1% of VOUT at final value.
7. Transition time >10 µs.
8. Half load to/from full load.
9. Measured from release of inhibit or input voltage step
Crane Aerospace & Electronics Power Solutions
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
TRIPLE OUTPUT MODEL SMRT283R312T 3.3 (MAIN) ±12 (AUXILIARIES)
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX
Output VOltage MAIN AND POS. AUX 3.23 3.30 3.37 11.76 12.00 12.24 VDC
NEG. AUX. -11.58 -12.00 -12.42
Output Current 2, 3 4.5 0 ±0.63 1 1
A
TOTAL 1.25
Output pOwer 2, 3 0 15 0 ±7.5 12 1
W
VIN = 19 t O 56 VDC TOTAL 15
Output rIpple 10 khz - 20 mhz 200 150 mV p-p
lIne regulatIOn MAIN AND POS. AUX 30 5 30 mV
VIN = 19, 50 VDC NEG. AUX. 10 70
lOaD regulatIOn MAIN AND POS. AUX 5 40 5 40
VIN = 19, 50 VDC 100 120
NEG. AUX. 1 10 300 mV
VIN = 19, 50 VDC 1 400
tOtal regulatIOn 1
VOUT
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
3.0 3.6 ±10.9 ±13.1 VDC
CrOSS regulatIOn 1, 4, 5
tC = 25°C
EFFECT ON
NEGATIVE AUXILIARY 2.5 %
Input VOltage COntInuOuS 19 28 56 VDC
tranSIent 120 ms 0 80 V
Input Current nO lOaD 110 mA
InhIbIteD 50
Input rIpple Current 610 kHz - 10 MHz 10 50 mA p-p
eFFICIenCy 768 %
lOaD Fault 8, 9 POWERDISSIPATION 28 W
reCOVery 1 25 25 ms
Step lOaD reSpOnSe 9, 10, 11 tranSIent ±450 ±450 mV pk
reCOVery 3 3 ms
Step lIne reSpOnSe 1, 8, 9 19 - 50 - 19 VIn
tranSIent ±500 ±750 mV pk
reCOVery 4 4 ms
Start-up 11 Delay
nO lOaD anD Full 35 25 ms
OVerShOOt 0 50 0 120 mV pk
CapaCItIVe lOaD 1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 1000 µF
Notes: See page 15
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
Crane Aerospace & Electronics Power Solutions
www.craneae.com/interpoint Page 13 of 22
SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
Notes: See page 15
TRIPLE OUTPUT MODEL SMRT283R315T 3.3 (MAIN) ±15 (AUXILIARIES)
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX
Output VOltage MAIN AND POS. AUX 3.23 3.30 3.37 14.70 15.00 15.30 VDC
NEG. AUX. -14.48 -15.00 -15.53
Output Current 2, 3 4.5 0 ±0.5 0.8 1
A
TOTAL 1.0
Output pOwer 2, 3 0 15 0 ±7.5 12 1
W
VIN = 19 t O 56 VDC TOTAL 15
Output rIpple 10 khz - 20 mhz 200 150 mV p-p
lIne regulatIOn MAIN AND POS. AUX 30 5 30 mV
VIN = 19, 50 VDC NEG. AUX. 10 70
lOaD regulatIOn MAIN AND POS. AUX 5 40 5 40
VIN = 19, 50 VDC 100 120
NEG. AUX. 1 300 mV
VIN = 19, 50 VDC 1 400
tOtal regulatIOn 1
VOUT
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
3.0 3.6 ±14.0 ±16.0 VDC
CrOSS regulatIOn 1, 4, 5
tC = 25°C
EFFECT ON
NEGATIVE AUXILIARY 2.5 %
Input VOltage COntInuOuS 19 28 56 VDC
tranSIent 120 ms 0 80 V
Input Current nO lOaD 110 mA
InhIbIteD 50
Input rIpple Current 610 kHz - 10 MHz 10 50 mA p-p
eFFICIenCy 768 %
lOaD Fault 8, 9 POWERDISSIPATION 28 W
reCOVery 1 25 25 ms
Step lOaD reSpOnSe 9, 10, 11 tranSIent ±450 ±450 mV pk
reCOVery 3 3 ms
Step lIne reSpOnSe 1, 8, 9 19 - 50 - 19 VIn
tranSIent ±500 ±750 mV pk
reCOVery 4 4 ms
Start-up 11 Delay
nO lOaD anD Full 35 25 ms
OVerShOOt 0 50 0 150 mV pk
CapaCItIVe lOaD 1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 1000 µF
Crane Aerospace & Electronics Power Solutions
www.craneae.com/interpoint Page 14 of 22
SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Notes: See page 15
TRIPLE OUTPUT MODEL SMRT28507T 5 (MAIN) ±7 (AUXILIARIES)
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX
Output VOltage MAIN AND POS. AUX 4.90 5.00 5.10 6.86 7.00 7.14 VDC
NEG. AUX. -6.79 7.00 -7.21
Output Current 2, 3 3.0 0 ±1.00 1.2 1
A
TOTAL 2.0
Output pOwer 2, 3 0 15 0 ±7.0 11.2 1
W
VIN = 19 t O 56 VDC TOTAL 14
Output rIpple 10 khz - 20 mhz 230 ±170 mV p-p
lIne regulatIOn MAIN AND POS. AUX 70 100 mV
VIN = 19, 50 VDC NEG. AUX. 150
lOaD regulatIOn MAIN AND POS. AUX 5 100 5 250
VIN = 19, 50 VDC 150 250
NEG. AUX. 1 350 mV
VIN = 19, 50 VDC 1 350
tOtal regulatIOn 1
VOUT
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
4.7 5.3 ±6.53 ±7.47 VDC
CrOSS regulatIOn 1, 4, 5
tC = 25°C
EFFECT ON
NEGATIVE AUXILIARY 2.5 %
Input VOltage COntInuOuS 19 28 56 VDC
tranSIent 120 ms 0 80 V
Input Current nO lOaD 110 mA
InhIbIteD 50
Input rIpple Current 610 kHz - 10 MHz 10 50 mA p-p
eFFICIenCy 771 %
lOaD Fault 8, 9 POWERDISSIPATION 22 W
reCOVery 1 25 25 ms
Step lOaD reSpOnSe 9, 10, 11 tranSIent ±300 ±400 mV pk
reCOVery 2 2 ms
Step lIne reSpOnSe 1, 8, 9 19 - 50 - 19 VIn
tranSIent ±500 ±750 mV pk
reCOVery 4 4 ms
Start-up 11 Delay
nO lOaD anD Full 20 20 ms
OVerShOOt 0 100 0 150 mV pk
CapaCItIVe lOaD 1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 1000 µF
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
Crane Aerospace & Electronics Power Solutions
www.craneae.com/interpoint Page 15 of 22
SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Notes: See page 15
TRIPLE OUTPUT MODEL SMRT28512T 5 (MAIN) ±12 (AUXILIARIES)
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX
Output VOltage MAIN AND POS. AUX 4.90 5.00 5.10 11.76 12.00 12.24 VDC
NEG. AUX. -11.58 -12.00 -12.42
Output Current 2, 3 3.0 0 ±0.63 11
A
MAX TOTAL AUX 1.25
Output pOwer 2, 3 0 15 0 ±7.5 12 1
W
VIN = 19 t O 56 VDC MAX TOTAL AUX 15
Output rIpple 10 khz - 20 mhz 200 150 mV p-p
lIne regulatIOn MAIN AND POS. AUX 30 5 30 mV
VIN = 19, 50 VDC NEG. AUX. 20 70
lOaD regulatIOn MAIN AND POS. AUX 5 40 5 40
VIN = 19, 50 VDC 100 120
NEG. AUX. 1 10 300 mV
VIN = 19, 50 VDC 1 400
tOtal regulatIOn 1
VOUT
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
4.7 5.3 ±10.9 ±13.1 VDC
CrOSS regulatIOn 1, 4, 5
tC = 25°C
EFFECT ON
NEGATIVE AUXILIARY 2.5 %
Input VOltage COntInuOuS 19 28 56 VDC
tranSIent 120 ms 0 80 V
Input Current nO lOaD 110 mA
InhIbIteD 50
Input rIpple Current 610 kHz - 10 MHz 10 50 mA p-p
eFFICIenCy 768 %
lOaD Fault 8, 9 POWERDISSIPATION 25 W
reCOVery 1 25 25 ms
Step lOaD reSpOnSe 9, 10, 11 tranSIent ±450 ±450 mV pk
reCOVery 3 3 ms
Step lIne reSpOnSe 1, 8, 9 19 - 50 - 19 VIn
tranSIent ±500 ±750 mV pk
reCOVery 4 4 ms
Start-up 11 Delay
nO lOaD anD Full 25 25 ms
OVerShOOt 0 50 0 120 mV pk
CapaCItIVe lOaD 1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 1000 µF
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
Crane Aerospace & Electronics Power Solutions
www.craneae.com/interpoint Page 16 of 22
SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24
Electrical Characteristics: -55°C to +125°C TC, 28 VDC Vin, 100% load, unless otherwise specified.
Notes: See page 15
TRIPLE OUTPUT MODEL SMRT28515T 5 (MAIN) ±15 (AUXILIARIES)
unItS
parameter COnDItIOnS MIN TYP MAX MIN TYP MAX
Output VOltage MAIN AND POS. AUX 4.92 5.00 5.08 14.77 15.00 15.23 VDC
NEG. AUX. -14.70 -15.00 -15.30
Output Current 2, 3 3.0 0 ±0.5 0.80 1
A
MAX TOTAL AUX. 1
Output pOwer 2, 3 0 15 0 ±7.5 11.25 1
W
VIN = 19 t O 56 VDC MAX TOTAL AUX 15
Output rIpple 10 khz - 20 mhz 200 200 mV p-p
lIne regulatIOn MAIN AND POS. AUX 5 25 25 mV
VIN = 19, 50 VDC NEG. AUX. 20 35
lOaD regulatIOn MAIN AND POS. AUX 5 50 5 50
VIN = 19, 50 VDC 100 120
NEG. AUX. 1 500 mV
VIN = 19, 50 VDC 1 600
tOtal regulatIOn 1
VOUT
all COnDItIOnS OF
lIne, lOaD, agIng,
temp anD raDIatIOn
4.7 5.3 ±14.0 ±16.0 VDC
CrOSS regulatIOn 1, 4, 5
tC = 25°C
EFFECT ON
NEGATIVE AUXILIARY 2.5 %
Input VOltage COntInuOuS 19 28 56 VDC
tranSIent 120 ms 0 80 V
Input Current nO lOaD 110 mA
InhIbIteD 50
Input rIpple Current 610 kHz - 10 MHz 10 150 mA p-p
eFFICIenCy 770 %
lOaD Fault 8, 9 POWERDISSIPATION 25 W
reCOVery 1 35 35 ms
Step lOaD reSpOnSe 9, 10, 11 tranSIent ±250 ±350 mV pk
reCOVery 1 1 ms
Step lIne reSpOnSe 1, 8, 9 19 - 50 - 19 VIn
tranSIent ±500 ±750 mV pk
reCOVery 1.5 1.5 ms
Start-up 11 Delay
nO lOaD anD Full 25 20 ms
OVerShOOt 0 200 0 350 mV pk
CapaCItIVe lOaD 1
tC = 25°C
unCOnDItIOnally
Stable, Start-up
Delay InCreaSeD
5000 1000 µF
Crane Aerospace & Electronics Power Solutions
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SMRT28 Single, Dual and Triple Space DC/DC Converters
28 VOLT INPUT 35 WATT SPACE QUALIFIED
SMRT28 Rev F - 2011.01.24