Crane Aerospace & Electronics Power Solutions
MTR Single, Dual and Triple DC/DC Converters
28 VOLT INPUT – 30 WATT
FEATURES
• –55° to +125°C operation
• 16 to 40 VDC input
• Fully isolated
• Magnetic feedback
• Fixed frequency 600 kHz typical
• Topology – Single Ended Forward
• 50 V for up to 50 ms transient protection
• Inhibit and synchronization functions
• Indefinite short circuit protection
• Up to 30 watts output power
• Trim and remote sense on single output models
• Up to 84% efficiency
MODELS
VDC O
UTPUT
SINGLE
DUAL
TRIPLE
3.3
±5
+5 & ±12
5
±12
+5 & ±15
12
±15
15
18
DESCRIPTION
The MTR Series™ of DC/DC converters offers up to 30 watts of
output power from single, dual, or triple output configurations. They
operate over the full military temperature range with up to 84% effi-
ciency. MTR converters are packaged in hermetically sealed metal
cases, making them ideal for use in military, aerospace and other
high reliability applications.
Indefinite short circuit protection and overload protection are
provided by a constant current-limit feature. This protective system
senses current in the converter’s secondary stage and limits it to
approximately 115% of the maximum rated output current.
MTR converters are provided with internal filtering capacitors that
help reduce the need for external components in normal operation.
For systems that require compliance with MIL-STD-461C’s CE03
standard, Interpoint offers filter/transient suppression modules
(including the FMC-461, FMD-461 and FM-704A series filters) which
will result in compliance. Contact your Interpoint representative for
further details.
C
ONVERTER
D
ESIGN
The MTR converters are constant frequency, pulse-width modulated
switching regulators which use a quasi-square wave, single ended,
forward converter design. Tight load regulation is maintained via
wide bandwidth magnetic feedback and, on single output models,
through use of remote sense. On dual output models, the positive
output is independently regulated and the negative output is cross
regulated through the use of tightly coupled magnetics and shunt
regulators. The MTR Series triple output DC/DC converter’s design
includes individual regulators on the auxiliary outputs which provide
for no cross regulation error when a minimum 500 mA load is main-
tained on the main (+5) output.
S
YNCHRONIZATION
Synchronizing the converter with the system clock allows the
designer to confine switching noise to clock transitions, minimizing
interference and reducing the need for filtering. In sync mode, the
converter will run at any frequency between 500 kHz and 675 kHz.
The sync control operates with a quasi-TTL signal at any duty cycle
between 40% and 60%. The sync pin must be connected to input
common pin when not in use.
Crane Aerospace & Electronics
Electronics Group (Interpoint Brand)
PO Box 97005 • Redmond WA 98073-9705
425.882.3100 • electronics@craneae.com
www.craneae.com
Page 1 of 19
Rev G - 20060505
Crane Aerospace & Electronics Power Solutions
MTR Single, Dual and Triple DC/DC Converters
28 VOLT INPUT – 30 WATT
OPERATING CONDITIONS AND CHARACTERISTICS
Input Voltage
• 16 to 40 VDC continuous
• 50 V for 50 msec transient
Output Power
• 25 to 30 watts depending on model
Lead Soldering Temperature (10 sec per pin)
• 300°C
Storage Temperature Range (Case)
• –65°C to +135°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
Output Voltage Temperature Coefficient
• 100 ppm/°C typical single and dual outputs
• 200 ppm/°C main typical, 300 ppm/°C aux
triple output typical
Input to Output Capacitance
• 50 pF typ (100 pF typical triple outputs)
Current Limit
• 115% of full load typical
Isolation
• 100 megohm minimum at 500 V
Audio Rejection
• 40 dB typ (50 dB typical triple output)l
Conversion Frequency
• Free run 550 min, 600 typical, 650 max kHz duals and singles
Free run 525 min, 600 typical, 650 max kHz triples
• External sync 500 to 675 kHz singles and duals
External sync 500 to 700 kHz triples
SYNC AND INHIBIT
Sync (500 to 675 kHz)
• Duty cycle 40% min, 60% max
• Logic low 0.8 V max
• Logic high 4.5 V min, 5 V max
• Referenced to input common
• If not used, connect to input common
Inhibit TTL Open Collector (referenced to input common)
• Logic low (output disabled), ≤0.8 V
Inhibit pin current
8.0 mA max for singles & duals,
6.0 mA for triples
• Logic high (output enabled)
Input pin voltage, unit enabled, 9 to 11 V
MECHANICAL AND ENVIRONMENTAL
Size (maximum)
Non-flanged
Single and dual output
2.125 x 1.125 x 0.400 inches (53.98 x 28.58 x 10.16 mm) See case H2 for dimensions.
MTR Dual with standard or ES screening, ht 0.417", (10.59 mm) See Case H4 for dimensions.
1.950 x 1.350 x 0.405 inches (49.53 x 34.29 x 10.29 mm) See case F1 for dimensions.
Triple output
Flanged
Single and dual output
2.910 x 1.125 x 0.400 inches (73.91 x 28.58 x 10.16 mm) See case K3 for dimensions.
MTR Dual with standard or ES screening, ht. 0.417", (10.59 mm) See case K5 for dimensions.
2.720 x 1.350 x 0.405 inches (69.09 x 34.29 x 10.29 mm) See case J1 for dimensions.
Triple output
Weight (maximum)
Single and dual non-flanged 50 grams, flanged 52 grams
Triple non-flanged 58 grams, flanged 62 grams
Screening
Standard, ES, or /883 (Class H, QML). See “883, Class H, QML Products – Element Evaluation” and “883, Class H, QML Products – Environmental
Screening” for more information.
www.craneae.com
Page 2 of 19
Rev G - 20060505
Crane Aerospace & Electronics Power Solutions
MTR Single, Dual and Triple DC/DC Converters
28 VOLT INPUT – 30 WATT
PIN OUT
Pin
1
2
3
4
5
6
7
8
9
10
Single Output
Positive Input
Inhibit
Sense Return
Output Common
Positive Output
Positive Sense
Case Ground
Case Ground
Sync
Input Common
Dual Output
Positive Input
Inhibit
Positive Output
Output Common
Negative Output
Case Ground
Case Ground
Case Ground
Sync
Input Common
Triple Output
Positive Input
Main (+5) Output
Output Common
Neg. Aux. Output
Pos. Aux. Output
Case Ground
Case Ground
Inhibit
Sync
Input Common
Inhibit
Sync In
Sense Lines
PINS NOT IN USE
Leave unconnected
Connect to input common
Must be connected to appropriate outputs
Dot on top of cover indicates pin one.
1
2
3
4
5
BOTTOM VIEW
MTR SINGLE
FLANGED AND NON-FLANGED
10
9
8
7
6
Dotted line outlines flanged package option.
See cases H2, H4, K3 and K5 for dimensions.
F
IGURE
1: P
IN
O
UT
S
INGLE
O
UTPUT
M
ODELS
Squared corner and dot on top
of package indicate pin one.
Dot on top of cover indicates pin one.
1
1
2
3
4
5
2
3
4
5
BOTTOM VIEW
MTR DUAL
FLANGED AND NON-FLANGED
10
9
8
7
6
BOTTOM VIEW
MTR TRIPLE
FLANGED AND NON-FLANGED
10
9
8
7
6
Dotted line outlines flanged package option.
See cases H2, H4, K3 and K5 for dimensions.
Dotted line outlines flanged package option.
See cases F1 and J1 for dimensions.
F
IGURE
2: P
IN
O
UT
D
UAL
O
UTPUT
M
ODELS
www.craneae.com
F
IGURE
3: P
IN
O
UT
T
RIPLE
O
UTPUT
M
ODELS
Page 3 of 19
Rev G - 20060505
Crane Aerospace & Electronics Power Solutions
MTR Single, Dual and Triple DC/DC Converters
28 VOLT INPUT – 30 WATT
MTR SINGLE OUTPUT CONVERTER
1
+VIN
OUTPUT
COMMON
SENSE
RETURN
SENSE
INPUT
COMMON
POSITIVE
OUTPUT
4
1
3
6
1
RT
5
RL
10
EXTERNAL TRIM CONNECTION
1 Make connections at converter.
Trim Formulas
Vout = desired output voltage; Rt = trim resistor
3.3V: Rt = 1300 * Vout – 4304
1.2475
5V: Rt = 1300 * Vout – 6512
1.2475
12V: Rt = 1300 * Vout – 15631
1.2475
15V: Rt = 1300 * Vout – 19498
1.2475
F
IGURE
4: T
RIM
C
ONNECTION1, 2, 3
MTR SINGLE OUTPUT CONVERTER
1
+VIN
OUTPUT
COMMON
SENSE
RETURN
SENSE
INPUT
COMMON
POSITIVE
OUTPUT
4
2
3
6
2
RL
10
5
REMOTE SENSE CONNECTION
2 Make connections at load.
F
IGURE
5: R
EMOTE
S
ENSE
C
ONNECTION
Notes for Remote Sense and Trim
1. When trimming output voltage and/or remote sensing, the total output
voltage increase must be less than 0.6 volts at the converters pins to
maintain specified performance.
2. If neither voltage trim nor remote sense will be used, connect pin 3 to
pin 4 and pin 5 to pin 6 or the output voltage will increase by 1.2 volts.
3. CAUTION: The converter will be permanently damaged if the positive
remote sense (pin 6) is shorted to ground. Damage may also result if
the output common or positive output is disconnected from the load with
the remote sense leads connected to the load.
www.craneae.com
Page 4 of 19
Rev G - 20060505
Crane Aerospace & Electronics Power Solutions
MTR Single, Dual and Triple DC/DC Converters
28 VOLT INPUT – 30 WATT
MODEL NUMBERING KEY
MTR
Base Model
Input Voltage
Output Voltage
(Main and aux. Vout for triple models)
Number of Outputs
(S = single, D = dual, T = triple)
Case Option
("F" indicates flanged option, non-flanged
case has no designator in this position)
Screening
(Standard screening has no designator
in this position.)
28 512 T
F / 883
SMD NUMBERS
S
TANDARD
M
ICROCIRCUIT
D
RAWING
(SMD)
5962-0150101HXC
5962-9306801HXC
5962-9306901HXC
5962-9307001HXC
5962-9320201HXC
5962-9320501HXC
5962-9307101HXC
5962-9307201HXC
5962-9307301HXC
5962-9307401HXC
MTR S
ERIES
S
IMILAR
P
ART
MTR283R3S/883
MTR2805S/883
MTR2812S/883
MTR2815S/883
MTR2818S/883
MTR2805D/883
MTR2812D/883
MTR2815D/883
MTR28512T/883
MTR28515T/883
To indicate the flanged case option change the “X” to “Z” In the SMD
number. The SMD number shown is for Class H screening, non-
flanged. 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
MTR28
Base model
Vout value
number of outputs
case option
screening
Choose one from each of the following rows
Vout value
Number of outputs
Case option
Screening
for singles or duals: 5, 12, or 15
S (single)
D (dual)
non-flanged case option, leave blank
standard screening, leave blank
for triples*: 512 or 515
or T (triple)
F (flanged case option)
/ES (ES screening), /883 (Class H, QML)
* for triple output models “5” indicates the main voltage, “12” or“15” indicate the ± auxiliary voltages.
www.craneae.com
Page 5 of 19
Rev G - 20060505