MFK281R8S Datasheet, PDF (1/23 Pages) Interpoint Corporation Company – MFK S ingle and D ual D C-DC Converters 16 to 50 vol ts i npu t – 25 Watt

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/in³
• Available to Class H, MIL-PRF-38534
• Undervoltage lockout
• -55°C to +125°C operation
• Fully isolated
• Magnetic feedback
• Fixed frequency, 500 kHz typical
• 65 volts for up to 1 sec. transient
protection
• Inhibit and sync function
• Output short circuit protection
models
Output Voltage (V)
SINGLE DUAL
1.8
±5
2.5
±7
3.3
±12
5
±15
5.2
5.7
12
15
28
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.
Converter Design
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.
Higher Power Density
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 in², this low profile package offers a total power
density of up to 42 watts per cubic inch.
Low Noise, High Audio Rejection
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.
Inhibit Function
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.
Synchronization
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.
Short Circuit Protection
MFK Series converters provide short circuit protection by
restricting the output current to approximately 115% of the full
load output current.
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.
Undervoltage Lockout
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.
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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MFK Rev AJ - 2016.04.25