PD - 94539
ASA28XXS SERIES
ADVANCED ANALOG
HIGH RELIABILITY
HYBRID DC/DC CONVERTERS
Description
The ASA28XXS Series of DC/DC converters are high
reliability thick film hybrid converters that use flyback
topology operating at a nominal frequency of 550Khz.
High input to output isolation is achieved through the
use of transformers in the flyback power and feedback
circuits.
The advanced feedback design provides fast loop re-
sponse for superior line and load transient characteris-
tics and offers greater reliability than devices incorpo-
rating optical feedback circuits.
This device is designed to meet MIL-STD-704D input
requirements offering full performance over a 16 to 40
volt input range. Output Power of up to 5 watts is avail-
able.
Connecting the inhibit pin (pin 5) to the input common
(pin 7) will cause the converter to shut down. It is rec-
ommended that the inhibit pin be driven by an open
collector device capable of sinking at least 400碌A. The
open circuit voltage of the inhibit pin is 11.5 鹵0.5 volts.
These converters are manufactured in a facility fully
qualified to MIL-PRF-38534. All processes used to
manufacture these converters have been qualified
thereby enabling Advanced Analog to deliver fully com-
pliant devices. Three standard temperature grades are
offered with the screening options. Refer to Screening
Level section. The CH grade converters are fully com-
pliant to MIL-PRF-38534 for class H. The HB grade
converters are processed with the same screening as
the CH grade, but do not have class H element evalua-
tion as required by MIL-PRF-38534. These two grades
are fully tested and operate over the full military tem-
perature range without derating of output power. A
commercial grade is also available. Variations in elec-
trical, mechanical and screening requirements can be
accommodated. Extensive computer simulation using
28V Input, Single Output
ASA
Features
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Up To 5 Watt Output Power
5, 12,15 Volt Outputs
High Reliability
Wide Input Voltage Range -16 To 40 Volts
Indefinite Short Circuit and Overload
Protection
Popular Industry Standard Pin-Out
Military Screening Available
Parallel Seam Welded Package
No External Capacitors Required
Input Voltage Surge Protected to
MIL-STD-704A
Under Voltage Lockout
Available as Standard Military Drawing
complex modeling allows design modifications
to be examined. Contact Advanced Analog with
specific requirements.
www.irf.com
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