Crane Aerospace & Electronics Power Solutions
MFK single and dual dC-dC Converters
16 tO 50 vOLts InPUt – 25 WAtt
Features
• 16 to 50 volt input
• Up to 87% efficiency, 42 W/in
3
• Undervoltage lockout
• Fully isolated
• Available to Class H, MIL-PRF-38534
O
utput
V
Oltage
(V)
MOdeLs
• -55°C to +125°C operation
SINGLE
1.8
2.5
3.3
5
5.2
5.7
12
15
28
DUAL
±5
±7
±12
±15
• Magnetic feedback
• 65 volts for up to 1 sec. transient
protection
• Inhibit and sync function
• Output short circuit protection
• Fixed frequency, 500 kHz typical
description
The Interpoint
®
MFK Series™ of high frequency dc-dc converters
offers a wide input voltage range of 16 to 50 volts and up
to 25 watts of output power. The converters are capable of
withstanding transients of up to 65 volts for up to one second.
The package is a hermetically sealed, welded metal case.
Flanged and non-flanged models are available.
C
onverter
D
esign
The MFK converters are switching regulators that use a quasi-
square wave, single-ended forward converter design with a
constant switching frequency of 500 kHz, typical. Isolation
between input and output circuits is provided with transformers in
the forward path and in the feedback control loop.
MFK 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 below 0.8 volts. The converter is enabled
when the pin, which is internally connected to a pull-up current
source, is left unconnected or is connected to an open-collector
gate. The open circuit voltage associated with the inhibit pin is
8.5 to 12 V. In the inhibit mode, a maximum of 4 mA must be
sunk from the inhibit pin. See Table 5 on page 5 for more
information.
i
nHibit
F
unCtion
s
ynCHronizAtion
H
igHer
P
ower
D
ensity
The MFK Series offers a new standard of performance for small
size and high power density. At just 0.360 inch high and a total
footprint of 1.7 in
2
, this low profile package offers a total power
density of up to 42 watts per cubic inch.
L
ow
n
oise
, H
igH
A
uDio
r
ejeCtion
A synchronization feature is included with the MFK Series that
allows the user to match the switching frequency of the converter
to the frequency of a system clock. Synchronization allows
the user to adjust the nominal 500 kHz operating frequency to
any frequency within the range of 450 kHz to 550 kHz. This is
initiated by applying an active high input of the desired frequency
to the sync pin. See Table 5 on page 5 for more information.
The MFK converters current mode control system provides
excellent dynamic response and noise rejection. Audio rejection
is typically 50 dB. Output voltage response for a 50% to 100%
step load transient is as low as 4% with a 400 µs recovery time.
The MFK Series converters are provided with internal filtering
capacitors that help reduce the need for external components
in normal operation. Use our FMCE-0328 EMI filter to meet
the requirements of MIL-STD-461C CE03 and CS01 and/or
MIL-STD-461D, E and F CE102 and CS101 levels of conducted
emissions.
Crane Aerospace & Electronics
Power Solutions – Interpoint Products
10301 Willows Rd. NE, Redmond, WA 98052
+1 425-882-3100 • power@crane-eg.com
www.craneae.com/interpoint
s
Hort
C
irCuit
P
roteCtion
MFK Series converters provide short circuit protection by
restricting the output current to approximately 115% of the full
load output current.
u
nDervoLtAge
L
oCkout
Undervoltage lockout with hysteresis prevents the converters
from operating below approximately 15 volts input voltage to
keep system current levels smooth, especially during initialization
or re-start operations.
MFK Rev AJ - 2016.04.25
Page 1 of 23
Crane Aerospace & Electronics Power Solutions
MFK single and dual dC-dC Converters
16 tO 50 vOLts InPUt – 25 WAtt
28 Volt input – 25 Watt
MOdeL nUMbeRIng Key
Base Model
Input Voltage
MFK
28 12
D
F / 883
S
tandard
M
icrOcircuit
d
rawing
(SMd)
5962-1421001HXC
5962-1421002HXC
5962-1421003HXC
5962-1421004HXC
5962-1421009HXC IN PROCESS
5962-1421005HXC
5962-1421006HXC
5962-1421007HXC
5962-1421008HTC
5962-1421101HXC
5962-1421102HXC
5962-1421103HXC
5962-1421104HXC
sMd nUMbeRs
MFK S
iMilar
p
art
MFK281R8S/883
MFK282R5S/883
MFK283R3S/883
MFK2805S/883
MFK285R2S/883
MFK285R7S/883
MFK2812S/883
MFK2815S/883
MFK2828S/883
MFK2805D/883
MFK2807D/883
MFK2812D/883
MFK2815D/883
Output Voltage
(R = decimal point, 3R3 = 3.3 Vout)
Number of Outputs
(S = single, D = dual)
Case Option
(Non-flanged case has no designator in
this position)
Screening
(Standard screening has no designator
in this position.)
F
igure
5: M
oDeL
n
uMbering
k
ey
The SMD number shown is for Class H screening, non-flanged. To
indicate the flanged case option change the “X” to “Z” In the SMD
number (“T” to “U” for 28 single). For exact specifications for an SMD
product, refer to the SMD drawing. SMDs can be downloaded from:
http://www.landandmaritime.dla.mil/programs/smcr
t
AbLe
3: sMD C
ross
r
eFerenCe
t
O
CAtegORy
base Model and
Input voltage
deterMine the MOdel nuMber enter One OptiOn FrOM
Output voltage
1
each categOry in the FOrM belOw
.
number of
Outputs
2
S
D
Case Options
3
screening
4
(standard, leave blank)
ES
883
MOdeL nUMbeR OPtIOns
options
FILL In FOR
MOdeL #
MFK28
1R8, 2R5, 3R3, 05
5R2, 5R7, 12, 15, 28
05, 07, 12, 15
(non-flanged, leave blank)
F (flanged)
MFK28
/
Notes
1. Output Voltage: An R indicates a decimal point. 1R8 is 1.8 volts out. The values of 1.8, 2.5, 3.3 and 5.7 volts are only available in single output models.
2. Number of Outputs: S is a single output and D is a dual output.
3. Case Options: For the standard case, Figure 32 on page 18 or Figure 33 on page 19, leave the case option blank. For the flanged case option, Figure 34 on
page 20 or Figure 35 on page 21, insert the letter F in the Case Option position.
4. Screening: For standard screening leave the screening option blank. For other screening options, insert the desired screening level. For more information see
Table 11 on page 22 and Table 12 on page 23.
t
AbLe
4: M
oDeL
n
uMber
o
Ptions
www.craneae.com/interpoint
MFK Rev AJ - 2016.04.25
Page 4 of 23
Crane Aerospace & Electronics Power Solutions
MFK single and dual dC-dC Converters
16 tO 50 vOLts InPUt – 25 WAtt
28 Volt input – 25 Watt
t
AbLe
5: o
PerAting
C
onDitions
, A
LL
M
oDeLs
, 25°C
CAse
, 28 v
in
, 100%
LoAD
,
unLess otHerwise sPeCiFieD
.
MFK 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
UNDERVOLTAGE LOCKOUT
CURRENT LIMIT
3
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
5
INHIBIT PIN PULLED LOW
4
INHIBIT PIN SOURCE
CURRENT
1
REFERENCED TO
INHIBIT ACTIVE HIGH (OUTPUT ENABLED)
Do not apply a voltage to the inhibit pin
5
OPEN PIN VOLTAGE
1
INHIBIT PIN CONDITION
—
—
% OF FULL LOAD
FULL POWER
ABSOLUTE
1
LINEARLY
MIL-STD-883, METHOD 3015
CLASS 2
500 VDC AT 25°C
ALL MODELS
CONDITIONS
10 SECONDS MAX.
MIN
—
-65
-55
-55
TYP
—
—
—
—
MAX
300
+150
+125
+135
UNITS
°C
°C
°C
From 100% at 125°C to 0% at 135°C
2000 - 3999
2
100
—
—
—
430
450
40
—
4.5
—
15
115
50
—
—
—
—
—
—
—
—
—
570
550
60
0.8
5.0
V
Megohms
V
%
dB
kHz
kHz
%
V
INPUT COMMON
LEAVE UNCONNECTED
—
—
0.8
4
V
mA
INPUT COMMON
OPEN COLLECTOR OR
UNCONNECTED
8.5
—
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 characterization test and/or analysis. Not a production test.
2. Passes 2000 volts.
3. Dual outputs: The over-current limit will trigger when the sum of the currents
from both outputs reaches 115% (typical value) of the maximum rated “total”
current of both outputs.
4. Tested with inhibit pin pulled to ground.
5. An external inhibit interface should be used to pull the inhibit low or leave it
floating. The inhibit pin can be left unconnected if not used.
www.craneae.com/interpoint
MFK Rev AJ - 2016.04.25
Page 5 of 23