MWR283 Datasheet, PDF (1/16 Pages) Interpoint Corporation Company – MWR Triple DC-DC Converters

Crane Aerospace & Electronics Power Solutions
MWR Triple DC-DC Converters
14 to 50 volt input-35 watt
Features
• Input voltage range 14 to 50 V
• Transient protection up to 80 V
for one second
• Output short circuit protection
• -55°C to +125°C operation
• Magnetic feedback
• Synchronization
• Inhibit function
• Up to 33 W/in³, 85% efficiency
• Undervoltage lockout
MODELS
Output voltage (V)
Triple
3.3 V ±12 V
3.3 V ±15 V
5 V ±12 V
5 V ±15 V
description
The MWR Series™ of high frequency DC-DC converters offers
a wide input voltage range of 14 to 50 volts and up to 35 watts
of output power. The units are capable of withstanding short
term transients up to 80 volts for one second. The package
is a hermetically sealed, welded metal case. Flanged and
non-flanged models are available.
Converter Design
MWR Series DC-DC converters are switching regulators that use
continuous flyback conversion topology with a clock frequency
of approximately 300 kHz. MWR Series converters incorporate
two internal converters with one converter phase shifted
approximately 120° from the other to create a dual phase/phase-
shifted operation. Each of the internal converters operates at the
clock frequency. This design provides completely independent
regulation with no cross regulation effect between the main
and auxiliary outputs and no minimum loading required on the
main output. The design minimizes input ripple, greatly reduces
output ripple and improves efficiency. See “Figure 1: MWR Block
Diagram” on page 2.
Low Noise, High Audio Rejection
The MWR converters’ feed-forward compensation system
provides excellent dynamic response and noise rejection. Audio
rejection is typically 40 dB.
The MWR Series converters are provided with internal filtering
capacitors that help reduce the need for external components
in normal operation. Use our FMCE-0528 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.
Inhibit Function
MWR 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 unit is enabled when
the pin, which is internally connected to a pull-up resistor, is left
unconnected or is connected to an open-collector gate. The open
circuit output 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.
Synchronization
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 c­ onverter will run at any frequency between 270
kHz and 330 kHz. The sync control operates with a duty cycle
between 40% and 60%.
Short Circuit Protection
MWR Series converters provide short circuit protection by
restricting the output current to approximately 150% of the
full load output current. The output current is sensed in the
secondary stage to provide highly predictable and accurate
current limiting, and to eliminate foldback characteristics. For
better protection, the current limit function of the main and the
auxiliary sides are linked together. If one output goes to current
limit, the other outputs will be turned off at the same time.
Undervoltage Lockout
Undervoltage lockout with hysteresis prevents the units from
operating below approximately 12 volts input voltage to keep
system current levels smooth, especially during initialization or
re-start operations.
Crane Aerospace & Electronics
Power Solutions – Interpoint Products
10301 Willows Rd. NE, Redmond, WA 98052
[phone] • [e-mail]
www.craneae.com/interpoint
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MWR Rev AD - 2016.05.20