PD - 94554A
AHE28XXS SERIES
28V Input, Single Output
ADVANCED ANALOG
HYBRID-HIGH RELIABILITY
DC/DC CONVERTERS
Description
The AHE28XXS Series of DC/DC converters feature
high power density and an extended temperature range
for use in military and industrial applications. Designed
to MIL-STD-704D input requirements, these devices
have nominal 28VDC inputs with +5V, +12V and +15V
single outputs to satisfy a wide range of requirements.
The circuit design incorporates a pulse width modu-
lated push-pull topology operating in the feed-forward
mode at a nominal switching frequency of 250KHz.
Input to output isolation is achieved through the use of
transformers in the forward and feedback circuits.
AHE
Features
n 17 to 40 VDC Input Range (28 VDC Nominal)
5V, 12V and 15V Outputs Available
n
n Indefinite Short Circuit and Overload
Protection
n 17 W/in3 Power Density
The advanced feedback design provides fast loop re-
sponse for superior line and load transient character-
istics and offers greater reliability and radiation toler-
ance than devices incorporating optical feedback cir-
cuits.
n 15 and 20 Watts Output Power Models
n Fast Loop Response for Superior Transient
Characteristics
n Operating Temperature Range from -55°C to
+125°C Available
Three standard temperature grades are offered with
screening options. Refer to Part Number section. They
can be provided in a standard plug-in package for PC
mounting or in a flanged package for more severe en-
vironments.
n Popular Industry Standard Pin-Out
n Resistance Seam Welded Case for Superior
Long Term Hermeticity
n Efficiencies up to 84%
n Shutdown from External Signal
n Military Screening
These converters are manufactured in a facility certi-
fied to MIL-PRF-38534. All processes used to manu-
facture these converters have been qualified to enable
Advanced Analog to deliver compliant devices.
n 325,000 hour MTBF at 85°C (AUC)
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 screen-
ing but do not have class H element evaluation as re-
quired by MIL-PRF-38534. Both grades are fully tested
and operate over the full military temperature range
without derating of output power. Variations in electri-
cal, mechanical and screening can be accommodated.
Extensive computer simulation using complex
modeling enables rapid design modification to
be provided. Contact Advanced Analog with spe-
cific requirements.
www.irf.com
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10/28/02