LAMBDA ADVANCED ANALOG INC.
λ
PRELIMINARY
AFL27003.3S Series
Single Output, Hybrid - High Reliability
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, +50, +120 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 Lambda Advanced Analog'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, soft-start
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 Lambda Advanced
Analog's rugged ceramic lead-to-package seal
assuring long term hermeticity in the most harsh
environments.
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-PRF-38534 for class H.
The HB grade is processed and screened to the
class H requirement, but may not necessarily meet
all of the other requirements, e.g., element
evaluation and Periodic Inspections (P.I.) not
required. 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 demanding
applications. Variations in electrical, mechanical
and screening can be accommodated. Contact
Lambda Advanced Analog for special requirements.
FEATURES
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
160 To 400 Volt Input Range
3.3 Volt Output
High Power Density - 50 W / in
3
66 Watt Output Power
Parallel Operation with Stress and Current
Sharing
Low Profile (0.380") Seam Welded Package
Ceramic Feedthru Copper Core Pins
High Efficiency - 72%
Full Military Temperature Range
Continuous Short Circuit and Overload
Protection
Remote Sensing Terminals
Primary and Secondary Referenced Inhibit
Functions
Line Rejection > 60 dB - DC to 50KHz
External Synchronization Port
Fault Tolerant Design
Dual Output Versions Available
Standard Military Drawings Available
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Soldering Temperature
Case Temperature
-0.5V to 500V
300°C for 10 seconds
Operating-55°C to +125°C
Storage -65°C to +135°C
AFL27003.3S
TABLE I. Electrical Performance Characteristics.
Test
Symbol
Conditions
-55°C
≤
T
C
≤
+125°C
V
IN
= 28 V dc
±5%,
C
L
= 0
unless otherwise specified
Group A
Subgroups
Device
Type
Limits
Unit
Min
3.27
Output voltage
V
OUT
I
OUT
= 0
1
2,3
Output current 6/
Output ripple voltage
Line regulation
I
OUT
V
RIP
VR
LINE
V
IN
= 16, 28, 40 v dc
V
IN
= 16, 28, 40 v dc
B.W.= 20 Hz to 10 MHz
V
IN
= 16, 28, 40 v dc
I
OUT
= 0, 10 A, and 20 A
Load regulation
VR
LOAD
V
IN
= 16, 28, 40 v dc
I
OUT
= 0, 10 A, and 20 A
I
N
1,2,3
01
1,2,3
1,2,3
1,2,3
01
01
01
01
3.23
Max
3.33
V
3.37
20
A
MV p-p
mV
30
±
10
±
35
mV
Input current
I
OUT
= No load
1
2,3,
01
15
17
3
5
mA
Inhibit 1, (pin 4) shorted to input
return (pin 2)
Inhibit 2, (pin 12) shorted to output
return (pin 8)
Input ripple current
I
RIP
I
OUT
= 20 A
B.W.= 20 Hz to 10 MHz
Efficiency
Isolation
E
FF
ISO
I
OUT
= 20 A
Input to output or any pin to case
(except pin 3) at
500 V dc, T
C
= +25°C
No effect on dc performance,
T
C
= +25°C
1,2,3
1,2,3
1,2,3
01
60
mA p-p
1,2,3
1
01
01
72
100
%
MΩ
Maximum
Capacitive load 1/
See footnotes at end of table.
C
L
4
01
10,000
µF
2
AFL27003.3S
TABLE I. Electrical Performance Characteristics - Continued.
Test
Symbol
Conditions
-55°C
≤
T
C
≤
+125°C
V
IN
=28 V dc
±5%,
C= 0
unless otherwise specified
Group A
subgroups
Device
type
Limits
Unit
Min
Max
Power dissipation load fault
P
D
Overload 6/
Short circuit
1,2,3
01
30
30
W
Current Limit Point 5/
I
CL
V
OUT
= 90% V
NOM
V
IN
= 28 V
1
2
3
01
115
105
125
125
%
115
140
600
700
+450
KHz
KHz
mV pk
Switching frequency
Sync frequency range
Output response to step
transient load changes 2/ 8/
F
S
I
OUT
= 20 A
1,2,3
4,5,6
4,5,6
01
01
01
500
500
-450
F
sync
VO
TLOAD
I
OUT
= 20 A
50% to/from 100%
10% to/from 50%
Recovery time, step
transient load changes 2/ 8/
TT
LOAD
50% to/from 100%
4,5,6
01
-450
+450
200
µs
10% to/from 50%
Input step 16 V to/from 40 V dc,
I
OUT
= 20 A
Input step 16 V to/from 40 V dc,
I
OUT
= 20 A
I
OUT
= 0 and 20 A
I
OUT
= 0 and 20 A
4,5,6
01
400
mV pk
Output response to transient
step line changes 1/ 2/ 3/
Recovery time transient step
line changes 1/ 2/ 3/
Turn on overshoot 4/
Turn on delay
4/
VO
TLINE
-500
500
TT
LINE
4,5,6
01
500
µs
VTon
OS
Ton
D
Tr
LF
4,5,6
4,5,6
4,5,6
01
01
01
01
50
50
300
250
120
120
mV pk
ms
ms
KHrs
Load fault recovery
MTBF
MIL-HDBK-217,
AIF @ Tc = 40°C
Notes:
1/
2/
3/
4/
5/
6/
7/
8/
9/
Parameters not 100% tested but are guaranteed to the limits specified in the table.
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.
Line transient transition time
≥10
microseconds.
Turn on delay is measured with an input voltage rise time of between 100 and 500 volts per millisecond.
Current limit point is that condition of excess load causing output voltage to drop to 90% of nominal.
Parameter verified as part of another test.
All electrical tests are performed with remote sense leads connected to the output lead at the load.
Input step transition time
≥100
microseconds.
Enable inputs internally pulled high. Nominal open circuit voltage = 4.0V
DC
.
3
AFL27003.3S Case Outlines
Case X
Case W
Pin Variation of Case Y
3.000
2.760
ø 0.128
0.050
0.250
0.250
0.050
12
7
0.25 typ
12
7
1
6
1.260 1.500
1.000
Ref
0.200 Typ
Non-cum
Pin
ø 0.040
1.000
2.500
0.220
0.220
2.800
0.525
Pin
ø 0.040
2.975 max
0.238 max
0.42
0.380
Max
0.380
Max
Case Y
1.150
0.300
ø 0.140
0.050
Case Z
Pin Variation of Case Y
0.050
0.250
0.250
1
6
1.500 1.750 2.00
1.000
Ref
0.200 Typ
Non-cum
Pin
ø 0.040
1.000
Ref
Pin
ø 0.040
1.750
2.500
0.375
0.220
0.220
0.36
2.800
2.975 max
0.525
0.238 max
0.380
Max
0.380
Max
Tolerances, unless otherwise specified:
.XX
.XXX
=
=
±0.010
±0.005
4
AFL27003.3S Pin Designation
Pin No.
1
2
3
4
5
6
7
8
9
10
11
12
Designation
Positive Input
Input Return
Case
Enable 1
Sync Output
Sync Input
Positive Output
Output Return
Return Sense
Positive Sense
Share
Enable 2
Available Screening Levels and Process Variations for AFL 27003.3S Series.
MIL-STD-883
Method
No
Suffix
-20 to +85°C
Requirement
Temperature Range
Element Evaluation
Internal Visual
Temperature Cycle
Constant Acceleration
Burn-in
Final Electrical (Group A)
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
& Specification
¬
ü
Cond B
500g
96hrs @ 125°C
ü
Cond C
Cond A
160hrs @ 125°C
-55, +25, +125°C
ü
Cond C
Cond A
160hrs @ 125°C
-55, +25, +125°C
25°C
25°C
Seal, Fine & Gross
External Visual
1014
2009
Cond C
¬
Cond A, C
ü
Cond A, C
ü
Cond A, C
ü
¬
per Commercial Standards
Part Numbering
AFL 270 05 S X / CH
Model
Input Voltage
270 = 270V
28 = 28V
Screening
Case Style
W, X, Y, Z
, ES
HB, CH
–
Output Voltage
03.3 = 03.3V, 05 = 5V,
06 = 6V, 09 = 9V
12 = 12V, 15 = 15V
28 = 28V
Outputs
S = Single
D = Dual
5
