Crane Aerospace & Electronics Power Solutions
MFL single and dual dc-dc converters
28 VoLt input - 65 Watt
Features
•
Parallel up to 3 converters—maximum
recommended power is 70% of the total
available power.
•
Operating temperature -55°C to +125°C
•
Qualified to MIL-PRF-38534 Class H
•
Input voltage range 16 to 40 volts
•
Transient protection up to 80 volts for 50 ms
•
Fully isolated, magnetic feedback
•
Fixed high switching frequency
- Converter will shut down at an input voltage
above approximately 45 volts
•
Remote sense and output trim on single
output models
•
Primary and secondary inhibit function
•
Synchronization input and output
•
Indefinite short circuit protection
MOdELS
OuTPuT VOLTagE (V)
SINgLE
3.3
5
12
15
28
duaL
±5
±12
±15
•
High power density with up to 85% efficiency
description
The Interpoint
®
MFL Series™ 28 volt dc-dc converters are rated
up to 65 watts output power over a -55°C to +125°C temperature
range with a 28 V nominal input. On dual output models, up to
70% of the rated output power can be drawn from either the
positive or negative outputs. The welded, hermetically sealed
package is 3.005 x 1.505 x 0.400 inches.
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.
S
creening
MFL converters are offered with standard screening, “ES” or fully
compliant to MIL-PRF-38534 Class H screening. See Table 9 on
page 13 and Table 10 on page 14 for more information.
i
nhibit
D
eSign
F
eatureS
The MFL Series converters have two inhibit terminals (INH1 and
INH2) that can be used to disable power conversion, resulting in
a very low quiescent input current. See Table 5 on page 6 for
specifications.
The MFL 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 MFL 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.
S
ync
Converters may be synced to an external clock (525 to 675 kHz)
or to one another by using the sync in or out pins. See Table 5
on page 6 for specifications.
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
Page 1 of 14
MFL Rev ad - 2016.02.19
Crane Aerospace & Electronics Power Solutions
MFL single and dual dc-dc converters
28 VoLt input - 65 Watt
S
enSe anD
t
rim
Single output models provide sense to maintain voltage at the
load. The converters output voltage can also be trimmed up. See
Figure 1.
The units designated as slaves have the MSTR/INH2 pin (pin
12) connected to the SNS RTN pin (pin 9) of the master unit.
Figure 2 on page 3 shows the typical setup for two or three
units in parallel.
a second slave unit may be placed in parallel with a master and
slave; this requires the TRI pin (pin 3) of the master unit to be
connected to the SNS RTN pins (pin 9), per Figure 2 on page
3.
In current sharing mode, the converters function as a current
source. For this reason it is important that their outputs be
connected to the common ground at all times to prevent an
excessively high voltage at their outputs.
c
urrent
S
haring anD
p
arallel
o
peration
For increased power parallel up to 3 converters. The maximum
recommended power is 70% of the total available power. Multiple
MFL converters may be used in parallel to drive a common
load. Only single output models with SENSE and SNS RTN can
be used in the share mode. In this mode of operation the load
current is shared by two or three MFL converters.
In current sharing mode, one MFL converter is designated as a
master. The SLaVE pin (pin 11) of the master is left unconnected
and the MSTR/INH2 pin (pin 12) of the master is connected to
the SLaVE pin (pin 11) of the slave units.
28V
Inhibit
Sync In
+
–
1
2
3
4
5
6
Positive Input
Input Common
TRI
INH1
Sync Out
Sync In
Pos. Sense
10
9
Sense Return
8
Output Common
7
Positive Output
MSTR/INH2
12
Slave
11
REMOTE SENSE CONNECTION
–
+
RL
28V
Inhibit
Sync In
+
–
1
2
3
4
5
6
Positive Input
Input Common
TRI
INH1
Sync Out
Sync In
MSTR/INH2
12
11
Slave
10
Pos. Sense
9
Sense Return
8
Output Common
7
Positive Output
RA
OUTPUT VOLTAGE ADJUST CONNECTION
–
+
RL
V
OuT
INCREaSE
VOLTS
0.1
0.2
0.3
0.4
0.5
3.3 V
66
131
196
262
349
5V
77
R
a
(Ω)
12 V
27
55
82
109
139
15 V
21
43
64
86
109
153
230
307
396
Notes
1. When using remote sense for voltage
compensation or when using remote sense
for trim, the output will drift over temperature.
Contact applications Engineering for more
information powerapps@crane-eg.com.
2. do not exceed the maximum rated power.
F
igure
1: S
enSe
c
onnectionS anD
t
rim
t
able
– S
ingle
o
utput
m
oDelS
www.craneae.com/interpoint
Page 2 of 14
MFL Rev ad - 2016.02.19
Crane Aerospace & Electronics Power Solutions
MFL single and dual dc-dc converters
28 VoLt input - 65 Watt
1
2
3
4
5
6
28V
Inhibit
Sync In
+
–
Positive Input
Input Common
TRI
INH1
Sync Out
Sync In
MSTR/INH2
12
Slave
11
Pos. Sense
Sense Return
Positive Output
10
9
8
7
MASTER
Output Common
CONNECT TRI ONLY WHEN 2 SLAVES ARE USED
1
2
3
4
5
6
+
RL
–
Positive Input
Input Common
TRI
INH1
Sync Out
Sync In
SLAVE 1
Output Common
8
7
Positive Output
Pos. Sense
10
Sense Return
9
MSTR/INH2
12
Slave
11
1
2
3
4
5
6
Positive Input
Input Common
TRI
INH1
Sync Out
Sync In
SLAVE 2
Output Common
8
7
Positive Output
Pos. Sense
10
Sense Return
9
MSTR/INH2
12
Slave
11
Notes
1. No one converter may carry more than its maximum rated current.
2. Individual converter operation, load and layout may affect the actual current shared. Contact applications Engineering for more
information at powerapps@crane-eg.com.
3. When paralleling SMFLs a diode is required at the input of each inhibit pin as SMFLs do not have an internal diode on the
inhibit pin.
F
igure
2: p
arallel
c
onnectionS
– S
ingle
o
utput
m
oDelS
www.craneae.com/interpoint
Page 3 of 14
MFL Rev ad - 2016.02.19
Crane Aerospace & Electronics Power Solutions
MFL single and dual dc-dc converters
28 VoLt input - 65 Watt
pin out
pin
1
2
3
4
5
6
7
8
9
10
11
12
single output
Positive Input
Input Common
Triple (TRI)
Inhibit 1 (INH1)
Sync Out
Sync In
Positive Output
Output Common
Sense Return
Positive Sense
Slave
Master/Inhibit 2
(MSTR/INH2)
MFL2828s only
Positive Input
Input Common
Triple (TRI)
Inhibit 1 (INH1)
Sync Out
Sync In
Positive Output
No connection
Output Common
No connection
Slave
Master/Inhibit 2
(MSTR/INH2)
t
able
1: p
in
o
ut
dual output
Positive Input
Input Common
Triple (TRI)
Inhibit 1 (INH1)
Sync Out
Sync In
Positive Output
Output Common
Negative Output
No connection
Slave
Master/Inhibit 2
(MSTR/INH2)
TRI
Inhibit 1 (INH1)
Sync Out
Sync In
Sense Return
Positive Sense
Slave
Master/Inhibit 2
(MSTR/INH2)
pins not in use
Leave unconnected
Leave unconnected
Leave unconnected
Connect to Input Common
Connect to Output Common
Connect to Positive Output
Leave unconnected
Leave unconnected
t
able
2: p
inS not in
u
Se
Angled corner indicates pin one.
1
2
3
4
5
6
12
11
TOP VIEW
MFL
(Pin side, marked side)
10
9
8
7
See Figure 18 on page 12 for dimensions
F
igure
3: p
in
o
ut
www.craneae.com/interpoint
Page 4 of 14
MFL Rev ad - 2016.02.19
Crane Aerospace & Electronics Power Solutions
MFL single and dual dc-dc converters
28 VoLt input - 65 Watt
ModeL nuMbering key
Base Model
Input Voltage
MFL
28 05 S / 883
S
tandard
M
icrocircuit
d
rawing
(SMd)
5962-0621301HXC
5962-9316301HXC
5962-9316201HXC
5962-9316101HXC
5962-9319101HXC
5962-9319201HXC
5962-9319301HXC
sMd nuMbers
MFL S
erieS
S
iMiLar
P
art
Output Voltage
MFL283R3S/883
MFL2805S/883
MFL2812S/883
MFL2815S/883
MFL2805d/883
MFL2812d/883
MFL2815d/883
Number of Outputs
(S = single, D = dual)
Screening
(Standard screening has no designator
in this position.)
F
igure
4: m
oDel
n
umbering
K
ey
The SMd number shown is for Class H screening. For
exact specifications for an SMd product, refer to the
SMd drawing. SMds can be downloaded from
www.landandmaritime.dla.mil/programs/smcr
t
able
3: SmD n
umber
c
roSS
r
eFerence
t
o
category
options
FiLL in For
ModeL #
deterMine the ModeL nuMber enter one oPtion FroM
each category in the ForM beLow
.
output Voltage
1
number of
outputs
2
S
d
screening
3
(standard, leave blank)
ES
883
MFL28
/
ModeL nuMber options
base Model and
input Voltage
3R3, 05, 12, 15, 28
MFL28
05, 12, 15
Notes
1. Output Voltage: an R indicates a decimal point. 3R3 is 3.3 volts out. The value of 3R3 is only available in single output models.
2. Number of Outputs: S is a single output and d is a dual output.
3. Screening: For standard screening leave the screening option blank. For other screening options, insert the desired screening
level. For more information see Table 9 on page 13 and Table 10 on page 14. MFL2828S is not available on an SMd.
t
able
4: m
oDel
n
umber
o
ptionS
www.craneae.com/interpoint
Page 5 of 14
MFL Rev ad - 2016.02.19