AHF2805S_17 Datasheet, PDF (1/20 Pages) International Rectifier – HYBRID-HIGH RELIABILITY DC-DC CONVERTER

HYBRID-HIGH RELIABILITY
DC-DC CONVERTER
PD-94541E
AHF SERIES
28V Input, Single/Dual Output
Description
The AHF Series of DC-DC converters feature single or dual
outputs over the full military temperature range. No derating
in output power is required, making them suitable for use in
rugged military applications. The low profile, small outline
package is ideally suited to the tight board space require-
ments of many industrial and aerospace applications.
Designed for nominal 28Vdc inputs, this family of converters
will meet the requirements of MIL-STD-704D. The basic cir-
cuit utilizes a pulse width modulated, feed-forward topology
at a nominal switching frequency of 550KHz. Input to output
isolation is achieved through the use of transformers in the
forward and feedback circuits.
The proprietary magnetic feedback circuit provides for an
extremely wide bandwidth control loop with a high phase
margin. The closed loop frequency response of this converter
family extends to approximately 50kHz, resulting in superior
line and load transient characteristics. This feedback method
is also inherently temperature and radiation insensitive. This
gives the AHF Series an important advantage over convert-
ers that incorporate opto-couplers in their design.
Manufactured in a facility fully qualified to MIL-PRF-38534,
these converters are fabricated utilizing DLA qualified process.
For available screening options, refer to device screening
table in the data sheet. Variations are electrical, mechanical
and screening can be accommodated.
Extensive computer simulation using complex modeling
enables rapid design modification to be provided. Contact IR
HiRel San Jose with specific requirements.
AHF
Features
 16V to 40V_DC Input Range (28V_DC Nominal)
 Single and Dual Outputs
 12W Output Power
 22.8W/in³ Power Density
 Low Input / Output Noise
(50mA / 60mV_P-P max. respectively)
 Indefinite Short Circuit and Overload Protection
 Wideband Control Loop for Superior Transient
Characteristics
 No derating for -55°C to +125°C Operation
 Constant Switching Frequency
(550kHz Nominal)
 Standard Microcircuit Drawings Available
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2017-05-08