Crane Aerospace & Electronics Power Solutions
MOR Single and Dual DC/DC Converters
28 Volt input – 120 Watt
Features
parallel operation with current share,
up to 5 units (540 watts)
• Operating temperature -55° to +125°C
• Input voltage 16 to 40 VDC
• Transient protection 50 V for 120 ms
• Fully isolated, magnetic feedback
• Fixed high frequency switching
• Remote sense on single output models
• Inhibit function
• Sync In and Sync Out
• Indefinite short circuit protection
output flexibility, trim of 60% to 110%
MoDELS
VDC oUTPUT
SingleS
• High power density with up to 87% efficiency
3.3
5
6.3
9.5
12
15
dualS
±3.3
±5
±6.3
±9.5
±12
±15
description
With up to 120 watts of output power, the MOR Series™ of DC/
DC converters operates from a standard 28 volt bus and offers
a wide input range of 16 to 40 VDC. Full operation over the
military temperature range, -55°C to +125°C, makes the MOR
Series an ideal choice for military, aerospace, space, and other
high reliability applications. In compliance with MIL-STD-704D,
the converters will withstand transients of up to 50 volts for up
to 120 milliseconds. Use Interpoint’s FMCE-1528 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.
The converters are offered with standard screening, “ES”
screening, or fully compliant to “883” MIL-PRF-38534 Class H
screening. Standard microcircuit drawings (SMD) are available.
The MOR Series converters incorporate a single-ended forward
topology which uses a constant frequency Pulse Width Modulator
(PWM) current mode control design and switches at 550 kHz,
nominal.
S
hort
C
irCuit
P
roteCtion
The converters also provide short circuit protection by restricting
the current to 125% of the full load output current, typical.
i
nhibit
F
unCtion
All models offer two inhibits, one referenced to input common
and one referenced sense return (single output models) or to
output common (dual output models). A remote sense function is
available on single output models.
t
rim
F
unCtion
Using the trim function, the MOR Series can provide any output
from 2 to 33 VDC. For example, trimming the two 15 volt outputs
of the 15 dual (MOR2815D) to 14 volts, and then stacking the
outputs will provide a 28 volt output.
o
utPut
V
oltage
o
PtionS
The MOR Series converters are capable of providing other
output voltage options in addition to those characterized on this
datasheet. Contact your sales representative to discuss other
output voltage options, www.interpoint.com/contacts.
uS P
atentS
Interpoint converters may use one or more of the following US
patents 5,521,807, 5,694,303, and 5,631,822.
Crane Aerospace & Electronics
Electronics Group (Interpoint Brand)
PO Box 97005 • Redmond WA 98073-9705
425.882.3100 • power@crane-eg.com
www.interpoint.com
Page 1 of 24
MOR Rev K - 20100422
Crane Aerospace & Electronics Power Solutions
MOR Single and Dual DC/DC Converters
28 VOlt input – 120 Watt
HoW to use tHe Functions
i
nPut
V
oltage
Steady state voltage range is 16 to 40 VDC. Transient range
is 40 to 50 V for a maximum of 120 msec. All models include
a soft-start function to prevent large current draw and minimize
overshoot.
t
rim
Both single and dual output models include a trim function.
Output voltage can be trimmed from 60% up to 110% of nominal
V out . When trimming up, do not exceed the maximum output
power. When trimming down, do not exceed the maximum
output current. See Figure 2.
3
Trim
emi i
nPut
F
ilterS
Internal 500 volt capacitors are connected between the case and
input common and between the case and output common.
Use Interpoint’s FMCE-1528 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. When using
an external input filter it is important that the case of the filter
and the case of the converter be connected through as low as
an impedance as possible. Direct connection of the baseplates
to chassis ground is the best connection. If connected by a
single trace, the trace should be as wide as it is long. See Figure
1.
1, 2, 3
Positive Input
Positive Output 10, 11, 12
1 Positive Input
MOR
Single
Output
Positive Output 7
Positive Sense 10
R
T
TRIM UP
Sense Return
Output Common
9
8
TRIM
DOWN
F
igure
2: t
rim
– S
ingle
On dual models the positive output is regulated and the negative
output is transformer coupled (cross-regulated) to the positive
output. When trimming the duals, both output voltages will be
adjusted equally. See Figure 3.
10 Trim
28V
FMCE-1528
EMI Filter
4, 5, 6
Input Common
Output Common
7, 8, 9
Case
Chassis Ground
MOR
Single or Dual
Output
R
T
2 Input Common
MOR
Dual
Output
Positive Output
Output Common
Negative Output
7
8
TRIM UP
TRIM DOWN
9
F
igure
1: e
xternal
F
ilter
C
onneCtion
F
igure
3: t
rim
– d
ual
trim FormulaS
Trim Up:
V
o
a =
,
1.0 ≤ a ≤ 1.1
V
o nominal
R
T
(kΩ) =
(
Example:
V
o nominal
= 5.0
,
V
o
= 5.25
,
a = 1.05
,
R
T
= 390 kΩ
Trim Down:
V
o
,
0.6 ≤ a ≤ 1.0
a =
V
o nominal
R
T
(kΩ) = 50 • a – 30
1–a
Example: V
o nominal
= 5.0
,
V
o
= 4.5
,
a = 0.9
,
R
T
= 150 kΩ
www.interpoint.com
V
o
– 1 • 20
2.5
– 50
(a -1)
)
Page 2 of 24
MOR Rev K - 20100422
Crane Aerospace & Electronics Power Solutions
MOR Single and Dual DC/DC Converters
28 VOlt input – 120 Watt
i
nhibit
1
and
2
u
nderVoltage
l
oCkout
Two inhibit terminals disable switching, resulting in no output
and very low quiescent input current. The two inhibit pins allow
access to an inhibit function on either side of the isolation barrier
to help maintain isolation.
An open collector is required for interfacing with both of the
inhibit pins. Applying an active low to either inhibit pin will inhibit
the converter. Leaving the pins open will enable the converter.
Inhibit 1 is referenced to Input Common. Inhibit 2 is refer-
enced to Sense Return for single output models and to Output
Common for dual output models.
The open circuit voltage (unit enabled) for Inhibit 1 is 13 V
and for Inhibit 2 it is up to 8 V. Leave the Inhibit pins uncon-
nected if not used. The required active low voltage level is 0.8
V maximum for Inhibit 1 and 0.2 V maximum for Inhibit 2. See
Figures 4 and 5.
Undervoltage lockout prevents the units from operating below
approximately 15.5 VDC input voltage to keep system current
levels smooth, especially during initialization or re-start opera-
tions.
S
ynC
i
n and
S
ynC
o
ut
The MoR converters can be synchronized to the system clock
by applying an active high sync signal to the Sync In pin. Sync
out can be used to synchronize other components to the MoR
converter’s switching frequency.
V
CC
~
5V
~
10 k
10 k
Sync In
Input
Common
330 pF
1.8 k
1k
Positive
Input
20 k
Inhibit 1
Input
Common
10 k
12V
F
igure
6: S
ynC
i
n
200
V
CC
The frequency range for external synchronization is 525 to 625
kHz. The requirements for an external signal are 15% to 50%
duty cycle, 0 ≤ L ≤ 0.8 V and 4.5 ≤ H ≤ 9 V. Both Sync In and
Sync Out are referenced to input common. Sync In should be
connected to input common if not used. See Figures 6 and 7.
V
CC
~
200
Ω
MOR Input Side
F
igure
4: i
nhibit
1
Sync Out
Input
Common
Current
Limit
V
S
~
10 k
F
igure
7: S
ynC
o
ut
Voltage
E/A
P
oSitiVe
o
utPut
, n
egatiVe
o
utPut and
o
utPut
C
ommon
Inhibit 2
Sense
Return
200
Feedback
output current is typically limited to 125% of maximum specified
current under short circuit or load fault conditions.
Single output models operate from no load to full load. Dual
output models with balanced loads operate from no load to full
load. For dual models with unbalanced loads, at least 10% of
the total output power must be drawn from the positive output
at all times, however, the negative output does not require a
minimum load. See note 4, cross regulation, under the Electrical
Characteristics Tables.
Page 3 of 24
MOR Rev K - 20100422
MOR Output Side - Single Output
F
igure
5: i
nhibit
2
www.interpoint.com
Crane Aerospace & Electronics Power Solutions
MOR Single and Dual DC/DC Converters
28 VOlt input – 120 Watt
P
aralleling
(S
hare
P
in
)
P
oSitiVe
S
enSe
, S
enSe
r
eturn
By using the Share pin, up to five single or dual converters
may be paralleled for a total output power of up to 540 watts,
depending on model. To calculate available power, multiply the
number of converters (up to five) by their maximum output power.
Multiply the result by 90% for total available power. See Figure
8 for the internal circuit. The converters will share within 10% of
each other at 25% to 90% rated power. MOR converters feature
true n+1 redundancy for reliability in critical applications. See
Figure 9 for the proper connections.
All Positive outputs and Positive Senses should be connected to
a common point. All Negative Outputs and Sense Returns should
be connected to a common point. The Share pin is referenced to
Sense Return. Leave the share pin floating (unconnected) if not
used. Also see Figure 9.
A special remote sensing feature maintains the desired output
voltage at the load. See Figure 9. When this feature is not used,
connect the sense lines to their respective output terminals. See
Figure 10. Remote sensing is available on single output models
only. Do not exceed 110% of Vout and do not exceed maximum
output power.
1
28V
6
4
2
Positive Input
Sync In
Inhbit 1
Positive Output
7
Positive Sense
10
Inhibit 2
12
Sense Return
9
Load
–
+
MOR
Single
Output
Input Common
Output Common
8
1
28V
6
4
2
Positive Input
Sync In
Inhbit 1
MOR
Dual
Output
Positive Output 7
Inhibit 2 12
Output Common 8
Negative Output 9
Load
+
0
Load
–
Input Common
F
igure
10: t
yPiCal
C
onneCtionS
Share
260 k
10 k
F
igure
8: S
hare
Sense
Return
i
nCreaSe
o
utPut
V
oltage by
S
taCking
o
utPutS
Outputs may be stacked to increase the output voltage using a
dual model.
Dual outputs may be stacked to double the output voltage. See
Figure 11.
1
Positive Input
28V
6 Sync In
5 Sync Out
2
Input Common
Positive Output
7
Positive Sense
10
Share
11
Sense Return 9
Output common
8
1
Positive Input
Positive Output 7
Inhibit 2
Output Common 8
Negative Output 9
Load
+
–
MOR
Dual Output
2
Input Common
1 Positive Input
6 Sync In
5 Sync Out
2
Input Common
Positive Output
7
Positive Sense
10
Share
11
Sense Return 9
Output common
8
+
Load
–
F
igure
11: S
taCked
o
utPutS
– d
ual
m
odel
1 Positive Input
6 Sync In
5 Sync Out
2
Input Common
Positive Output
7
Positive Sense
10
Share
11
9
8
Sense Return
Output common
F
igure
9: P
aralleling
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Page 4 of 24
MOR Rev K - 20100422
Crane Aerospace & Electronics Power Solutions
MOR Single and Dual DC/DC Converters
28 VOlt input – 120 Watt
Block Diagram
Positive
Input
1.7 µH
0.5 µH
100
Ω
6 µF
100
Ω
0.015 µF
500 V
FET
Driver
+
_
Secondary VCC
Positive
Output
Positive
Sense
Sense
Return
Output
Common
Share
6 µF
0.1 Ω
Input
Common
0.015 µF
500 V
Bias
Supply
Inhibit 1
Share
Function
VS+
VIn
UVLO
PWM
Controller
+
_
VRef
Trim
Sync In
Sync Out
Secondary VCC
Sync
In / Out
Inhibit 2
F
igure
12: mor S
ingle
o
utPut
b
loCk
d
iagram
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Page 5 of 24
MOR Rev K - 20100422