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11/20/02
www.irf.com
1
ADVANCED ANALOG
HYBRID-HIGH RELIABILITY
DC/DC CONVERTERS
ATO28XXT SERIES
28V Input, Triple Output
Description
16 to 40 VDC Input Range (28VDC Nominal)
5V, ±12V or 5V, ±15V Outputs Available
Indefinite Short Circuit and Overload
Protection
15 Watts Output Power
Fast Loop Response for Superior Transient
Characteristics
Operating Temperature Range from -55°C to
+125°C Available
Popular Industry Standard Pin-out
Resistance Seam Welded Case for Superior
Long Term Hermeticity
Efficiencies up to 81%
Shutdown from External Signal
200,000 Hour MTBF at 85°C
Features
ATO
Three standard temperature grades are offered. Refer
to Part Number section. They are provided in a stan-
dard plug-in package for PC mounting or in a flanged
package for more severe environments.
These converters are manufactured in a facility fully
qualified to MIL-STD-1772. All processes used to manu-
facture these converters have been qualified to enable
Advanced Analog to deliver compliant devices. Two
screening grades are available to satisfy a wide range
of requirements. The CH grade converters are fully
compliant to MIL-PRF-38534 for class H. The HB grade
converters are processed to full class H screening re-
quirements but do not have class H element evalua-
tion as directed by MIL-PRF-39534. Both grades are
fully tested and operate over the full military tempera-
ture range without derating of output power. Variations
in electrical, mechanical and screening can be accom-
modated. Extensive computer simulation using com-
plex modeling enables modest design modifications to
be accommodated. Contact Advanced Analog with
specific requirements.
PD - 94582
The ATO28XXT Series of DC/DC converters feature
high power density and an extended temperature range
for use in military and industrial applications. Designed
to the nominal input requirements of MIL-STD-704D,
these devices have nominal 28VDC inputs with +5V
and
±
12V or +5V and
±
15V triple outputs to satisfy a
wide range of requirements. The circuit design incor-
porates a pulse width modulated push-pull topology
operating in the feed-forward mode at a nominal switch-
ing frequency of 250KHz. Input to output isolation is
achieved through the use of transformers in the for-
ward and feedback circuits.
The advanced feedback design provides fast loop re-
sponse for superior line and load transient characteris-
tics and offers greater reliability and radiation toler-
ance than devices incorporating optical feedback cir-
cuits.