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 400µA. The
open circuit voltage of the inhibit pin is 11.5 ±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.
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09/11/02
ASA28XXS Series
Notes to Specifications
1.
2.
3.
Parameter guaranteed and measured during line and load regulation tests.
Bandwidth guaranteed by design. Tested for 20 kHz to 2 MHz.
Capacitive load may be any value from 0 to the maximum limit without compromising dc performance. A capacitive load in excess
of the maximum limit will not disturb loop stability but may interfere with the operation of the load fault detection circuitry,
appearing as a short circuit during turn-on.
Parameter shall be tested as part of design characterization and after design or process changes.
An overload is that condition of load in excess of rated load but less than that necessary to trigger the short circuit protection
and is the condition of maximum power dissipation.
Load step transition time between 2 and 10 microseconds.
Recovery time is measured from the initiation of the transient to where V
OUT
has returned to within ±1 percent of V
OUT
at 50
percent load.
Input step transition time between 2 and 10 microseconds.
Turn-on delay time measurement is for either a step application of power at the input or the removal of a ground signal from the
inhibit pin (pin 2) while power is applied to the input.
4.
5.
6.
7.
8.
9.
Available Screening Levels and Process Variations for ASA28XXS Series
MIL-STD-883
Method
No
Suffix
-20°C to +85°C
ES
Suffix
-55°C to +125°C
HB
Suffix
-55°C to +125°C
CH
Suffix
-55°C to +125°C
MIL-PRF-38534
2017
1010
2001,
1015
MIL-PRF-38534
1014
2009
48hrs @ 85°C
25°C
Cond C
¬
¬
ü
Cond B
500g
48hrs @ 125°C
25°C
Cond A, C
ü
ü
Cond C
Cond A
160hrs @ 125°C
-55, +25, +125°C
Cond A, C
ü
ü
Cond C
Cond A
160hrs @ 125°C
-55, +25, +125°C
Cond A, C
ü
Requirement
Temperature Range
Element Evaluation
Internal Visual
Temperature Cycle
Constant Acceleration
Burn-in
Final Electrical (Group A)
Seal, Fine & Gross
External Visual
*
per Commercial Standards
Available Standard Military Drawing (SMD) Cross Reference
ASA2805S/CH
ASA2812S/CH
ASA2815S/CH
5962-9462901
5962-9463101
5962-9463001
Part Numbering
ASA 28 05 S / CH
Model
Input Voltage
28 = 28V
Screening
–
, ES, HB, CH
Output Voltage
5 = ±5, 12 = ±12,
15 = ±15
Outputs
S = Single
D = Dual
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