
PD - 94462E
AFL27003R3S
HIGH RELIABILITY
HYBRID DC/DC CONVERTER
Description
The AFL Series of DC/DC converters feature high power
density with no derating over the full military temperature
range. This series is offered as part of a complete family
of converters providing single and dual output voltages
and operating from nominal +28 or +270 volt inputs with
output power ranging from 80 to 120 watts. For
applications requiring higher output power, multiple
converters can be operated in parallel. The internal
current sharing circuits assure equal current distribution
among the paralleled converters. This series
incorporates International Rectifier’s proprietary
magnetic pulse feedback technology providing optimum
dynamic line and load regulation response. This
feedback system samples the output voltage at the pulse
width modulator fixed clock frequency, nominally 550
KHz. Multiple converters can be synchronized to a system
clock in the 500 KHz to 700 KHz range or to the
synchronization output of one converter. Undervoltage
lockout, primary and secondary referenced inhibit, softstart and load fault protection are provided on all models.
These converters are hermetically packaged in two
enclosure variations, utilizing copper core pins to
minimize resistive DC losses. Three lead styles are
available, each fabricated with International Rectifier’s
rugged ceramic lead-to-package seal assuring long
term hermeticity in the most harsh environments.
Manufactured in a facility fully qualified to MIL-PRF38534, 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-PRF38534 for class H. The HB grade is fully processed and
screened to the class H requirement, but does not have
material element evaluated to the class H requirement.
Both grades are tested to meet the complete group “A”
test specification over the full military temperature range
without output power deration. Two grades with more
limited screening are also available for use in less
270V Input, 3.3V Output
AFL
Features
n 160 To 400 Volt Input Range
n 3.3 Volt Output
n High Power Density - 46 W / in
n 66 Watt Output Power
n Parallel Operation with Stress and Current
Sharing
n Low Profile (0.380") Seam Welded Package
n Ceramic Feedthru Copper Core Pins
n High Efficiency - to 74%
n Full Military Temperature Range
n Continuous Short Circuit and Overload
Protection
n Remote Sensing Terminals
n Primary and Secondary Referenced
Inhibit Functions
n Line Rejection > 60 dB - DC to 50KHz
n External Synchronization Port
n Fault Tolerant Design
n Dual Output Versions Available
n Standard Military Drawings Available
demanding applications. Variations in electrical,
mechanical and screening can be accommodated.
Contact IR Santa Clara for special requirements.
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09/01/04

AFL27003R3S
Specifications
ABSOLUTE MAXI MUM RATI NGS
Input Voltage -0.5V to 500V
Soldering Temperature 300°C for 10 seconds
Case Temperature Operating -55°C to +125°C
Electrical Performance Characteristics -55°C < T
Parameter
INPUT VOLTAGE Note 6 160 270 400 V
OUTPUT VOLTAGE
OUTPUT CURRENT
OUTPUT POWER
MAXIMUM CAPACITIVE LOAD
OUTPUT VOLTAGE
TEMPERATURE COEFFICIENT
OUTPUT VOLTAGE REGULATION
Line
Load
OUTPUT RIPPLE VOLTAGE
INPUT CURRENT
No Load
Inhibit 1
Inhibit 2
INPUT RIPPLE CURRENT
CURRENT LIMIT POINT
Expressed as a
Percentage
of Full Rated Load
LOAD FAULT POWER
DISSIPATION
Overload or Short Circuit
EFFICIENCY
SWITCHING FREQUENCY
ISOLATION
MTBF
For Notes to Specifications, refer to page 3
Storage -65°C to +135°C
< +125°C, 160V< V
CASE
Group A
Subgroups
VIN = 270 Volts, 100% Load
1
2, 3
VIN = 160, 270, 400 Volts, Note 6
Note 6 66 W
4 Note 1 10,000
VIN = 270 Volts, 100% Load - Note 1, 6
1, 2, 3
1, 2, 3
1, 2, 3
2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3 500 550 600 KHz
No Load, 50% Load, 100% Load
VIN = 160, 270, 400 Volts
VIN = 160, 270, 400 Volts, 100% Load,
BW = 10MHz
VIN = 270 Volts
1
I
= 0
OUT
Pin 4 Shorted to Pin 2
Pin 12 Shorted to Pin 8
VIN = 270 Volts, 100% Load
B.W. = 10MHz
V
= 90% V
OUT
1
2
3
V
= 270 Volts
IN
VIN = 270 Volts, 100% Load
1 Input to Output or Any Pin to Case
(except Pin 3). Test @ 500VDC
MIL-HDBK-217F, AIF @ TC = 40°C
Test Conditions
Note 5
NOM
< 400V unless otherwise specified.
IN
Min Nom Max Unit
3.27
3.23
-0.015 +0.015 %/°C
-10.0
-35.0
115
105
125
72
100
300 KHrs
3.30
20 A
74
3.33
3.37
+10.0
+35.0
30 mVpp
15.0
17.0
3.00
5.00
60 mApp
125
115
140
30
V
V
µfd
mV
mV
mA
mA
mA
mA
%
%
%
W
%
MΩ
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Elecrical Performance Characteristics (Continued)
AFL27003R3S
Parameter
ENABLE INPUTS
Sink Current
Converter On
Sink Current
SYNCHRONIZATION INPUT
Pulse Amplitude, Hi
Pulse Amplitude, Lo
Pulse Rise Time
Pulse Duty Cycle
LOAD TRANSIENT RESPONSE
Amplitude
Recovery
Amplitude
Recovery
LINE TRANSIENT RESPONSE
Amplitude
Recovery
TURN-ON CHARACTERISTICS
Overshoot
Delay
LOAD FAULT RECOVERY
LINE REJECTION
Notes to Specifications:
(Inhibit Function)
Converter Off
Frequency Range
Group A
Subgroups
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
4, 5, 6
4, 5, 6
4, 5, 6
4, 5, 6
4, 5, 6
4, 5, 6
Logical Low, Pin 4 or Pin 12
Note 1
Logical High, Pin 4 and Pin 12 - Note 9
Note 1
Note 1
Note 1
Note 2, 8
Load Step 50% ⇔ 100%
Load Step 10% ⇔ 50%
Note 1, 2, 3
VIN Step = 160 ⇔ 400 Volts
VIN = 160, 270, 400 Volts. Note 4
Enable 1, 2 on. (Pins 4, 12 high or open)
Same as Turn On Characteristics.
MIL-STD-461, CS101, 30Hz to 50KHz
Note 1
Test Conditions
Min Nom Max Unit
-0.5
2.0
75
500
2.0
-0.5
20
-450
-450
-500
50
60 70 dB
1. Parameters not 100% tested but are guaranteed to the limits specified in the table.
2. Recovery time is measured from the initiation of the transient to where V
has returned to within ±1% of V
OUT
at 50% load.
3. Line transient transition time ≥ 100 µSec.
4. Turn-on delay is measured with an input voltage rise time of between 100 and 500 volts per millisecond.
5. Current limit point is that condition of excess load causing output voltage to drop to 90% of nominal.
6. Parameter verified as part of another test.
7. All electrical tests are performed with the remote sense leads connected to the output leads at the load.
8. Load transient transition time ≥ 10 µSec.
9. Enable inputs internally pulled high. Nominal open circuit voltage ≈ 4.0VDC.
0.8
100
50
100
700
10
0.8
100
80
450
200
450
400
500
500
250
120
V
µ
A
V
µA
KHz
V
V
nSec
%
mV
µSec
mV
µ
Sec
mV
µSec
mV
mSec
OUT
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