
07/09/02
www.irf.com
1
ADVANCED ANALOG
HIGH RELIABILITY
HYBRID DC/DC CONVERTERS
AFL50XXS SERIES
50V Input, Single Output
The AFL Series of DC/DC converters feature high power
density with no derating over the full military tempera-
ture range. This series is offered as part of a complete
family of converters providing single and dual output
voltages and operating from nominal +28, +50, +120 or
+270 volt inputs with output power ranging from 80 to
120 watts. For applications requiring higher output
power, individual converters can be operated in paral-
lel. The internal current sharing circuits assure equal
current distribution among the paralleled converters. This
series incorporates Advanced Analog’s proprietary mag-
netic pulse feedback technology providing optimum
dynamic line and load regulation response. This feed-
back system samples the output voltage at the pulse
width modulator fixed clock frequency, nominally 550
KHz. Multiple converters can be synchronized to a sys-
tem clock in the 500 KHz to 700 KHz range or to the
synchronization output of one converter. Undervoltage
lockout, primary and secondary referenced inhibit, soft-
start and load fault protection are provided on all mod-
els.
These converters are hermetically packaged in two en-
closure variations, utilizing copper core pins to mini-
mize resistive DC losses. Three lead styles are avail-
able, each fabricated with Advanced Analog’s rugged
ceramic lead-to-package seal assuring long term
hermeticity in the most harsh environments.
Description
30 To 80 Volt Input Range
3.3
,
5, 8, 9 12, 15, 24
and
28
Volts Outputs
Available
High Power Density - up to 84 W / in3
Up To 120 Watt Output Power
Parallel Operation with Stress and Current
Sharing
Low Profile (0.380") Seam Welded Package
Ceramic Feedthru Copper Core Pins
High Efficiency - to 85%
Full Military Temperature Range
Continuous Short Circuit and Overload
Protection
Remote Sensing Terminals
Primary and Secondary Referenced
Inhibit Functions
Line Rejection > 40 dB - DC to 50KHz
External Synchronization Port
Fault Tolerant Design
Dual Output Versions Available
Standard Military Drawings Available
Features
AFL
Manufactured in a facility fully qualified to MIL-PRF-
38534, these converters are available in four screening
grades to satisfy a wide range of requirements. The CH
grade is fully compliant to the requirements of MIL-H-
38534 for class H. The HB grade is fully processed and
screened to the class H requirement, may not neces-
sarily meet all of the other MIL-PRF-38534 requirements,
e.g., element evaluation and Periodic Inspection (P.I.)
not required. Both grades are tested to meet the com-
plete group “A” test specification over the full military
temperature range without output power deration.
available for use in less demanding applications.
Variations in electrical, mechanical and screen-
ing can be accommodated. Contact Advanced
Analog for special requirements.
PD - 94457A