PD - 94555A
AHE28XXD SERIES
HYBRID-HIGH RELIABILITY
DC/DC CONVERTERS
28V Input, Dual Output
Description
The AHE 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 +5.0V, +12V and +15V dual
outputs to satisfy a wide range of requirements. The
circuit design incorporates a pulse width modulated
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.
The advanced feedback design provides fast loop
response for superior line and load transient characteristics
and offers greater reliability and radiation tolerance
than devices incorporating optical feedback circuits.
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
be necessarily meet all of the other MIL-PRF-38534
requirements, e.g., element evaluation and Periodic
Inspection (P.I.) are 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 IR Santa Clara for special
requirements.
AHE
Features
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17 to 40 VDC Input Range
28 VDC Nominal Input
± 5.0V, ±12V and ±15V Outputs Available
Indefinite Short Circuit and Overload
Protection
3
12.9 W/in Power Density
15 Watts Output Power
Fast Loop Response for Superior Transient
Characteristics
Operating Temperature Range from -55°C to
+125°C Available
Popular Industry Standard Pin-Out
Resistance Seam Welded Case for Superior
Long Term Hermeticity
Efficiencies up to 82%
Shutdown from External Signal
Military Screening
314,000 hour MTBF at 85°C (AUC)
www.irf.com
1
04/01/04
AHE28XXD Series
Specifications
n
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Soldering Temperature
Case Temperature
-0.5V to 50V
300°C for 10 seconds
Operating -55°C to +125°C
Storage -65°C to +135°C
AHE2805D
Table I. Electrical Performance Characteristics
Test
Symbol
Conditions
-55°C
≤
Tc
≤+125°C
Vin = 28 Vdc ±5%, C
L
= 0
Unless otherwise specified
I
OUT
= 0
V
IN
= 17, 28, and 40 V dc
V
IN
= 17, 28, and 40 V dc,
B.W. = DC to 2MHz
V
IN
=17,28, and 40 V dc
V
IN
= 17, 28, and 40 V dc,
I
out
= 0,
±313,
and
±625mA
V
IN
= 17, 28, and 40 V dc,
I
OUT
= 0,
±313,and ±625
mA
I
OUT
= 0, inhibit (pin 2)
tied to input return (pin 10)
I
OUT
= 0,
inhibit (pin 2) = open
I
OUT
=
±625mA
B.W. = DC to 2MHz
I
OUT
=
±625mA
T
C
= +25°C
Input to output or any pin
to case (except pin 8)
at 500V dc Tc = +25ºC
No effect on dc
performance,
Tc = +25ºC
3
Overload, T
C
= +25°C
Short circuit, T
C
= +25°C
I
OUT
=
±625mA
50% load to/from100%load
No load to/from 50% load
Group A
Subgroups
Device
Types
Limits
Unit
Output voltage
Output current
9, 11
8, 9
V
OUT
I
OUT
V
RIP
P
OUT
VR
LINE
VR
LOAD
I
IN
1
2,3
1,2,3
1,2,3
1,2,3
1
2,3
1,2,3
1,2,3
All
All
All
All
All
All
All
Min
±4.95
±4.90
0.0
Max
±5.05
±5.10
±625
60
V
mA
mVp-p
W
mV
mV
mA
Output ripple voltage
Output power
9
Line
10
Regulation
Load
9
Regulation
Input current
4, 9, 11
15
25
50
110
18
40
Input ripple current
Efficiency
Isolation
Capacitive load
8
I
RIP
E
FF
ISO
1,2,3
1
1
4
1
1
4,5,6
4
5,6
4
5,6
All
All
All
All
All
01
02
03
All
All
225
225
250
-300
-450
-500
-750
80
100
50
mAp-p
%
MΩ
6, 12
C
L
P
D
9
200
6
6
275
245
275
+300
+450
+500
+750
µF
W
kHz
mVpk
Power dissipation
load fault
Switching frequency
F
S
VO
TLOAD
Output response to step
7
transient load changes
For Notes to Specifications, refer to page 3
2
www.irf.com
AHE28XXD Series
Table I. Electrical Performance Characteristics -
continued
Test
Symbol
Conditions
-55°
≤Tc ≤+125°C
Vin = 28 Vdc ±5%, C
L
= 0
unless otherwise
specified
50% load to/from 100%
load
Group A
Subgroups
Device
Types
Limits
AHE2805D
Unit
Min
Recovery time step
transient load
1, 7
changes
TT
LOAD
4
All
Max
70
µs
Output response
transient step line
5, 12
changes
Recovery time
transient step
1, 5, 12
line changes
Turn on overshoot
2, 9
Turn on delay
9
VO
TLINE
No load to 50% load
50% load to no load
Input step 17 to 40V dc
5,6
4,5,6
4,5,6
4,5,6
All
All
All
100
1500
5
1200
ms
mVpk
TT
LINE
Input step 40 to 17V dc
Input step 17 to 40V dc
4,5,6
4,5,6
All
All
-1500
4
ms
VTon
OS
Ton
D
12
Input step 40 to 17V dc
I
OUT =
0 and
±625mA
I
OUT
= 0 and
±625mA
4,5,6
4,5,6
4,5,6
4,5,6
All
All
All
All
4
600
10
10
mVpk
ms
ms
Load fault recovery
Tr
LF
Notes to Specifications
1
2
3
4
5
6
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.
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.
An overload is that condition with a load in excess of the rated load but less than that necessary to trigger the short circuit
protection and is the condition of maximum power dissipation.
Total power at both outputs. For operation at 16 V dc input, derate output power by 33 percent.
Input step transition time between 2 and 10 microseconds.
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.
Load step transition time between 2 and 10 microseconds.
Bandwidth guaranteed by design. Tested for 20 KHz to 2MHz.
Tested at each output.
When operating with unbalanced loads, at least 25 percent of the load must be on the positive output to maintain regulation.
Parameter guaranteed by line and load regulation tests.
Parameter shall be tested as part of design characterization and after design or process changes. Thereafter parameters shall be
guaranteed to the limits specified in Table I.
7
8
9
10
11
12
www.irf.com
3
AHE28XXD Series
Specifications
n
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Soldering Temperature
Case Temperature
-0.5V to 50V
300°C for 10 seconds
Operating -55°C to +125°C
Storage -65°C to +135°C
AHE2812D
Table II. Electrical Performance Characteristics
Test
Symbol
Conditions
-55°C
≤
Tc
≤+125°C
Vin = 28 Vdc ±5%, C
L
= 0
Unless otherwise specified
I
OUT
= 0
V
IN
= 17, 28, and 40 V dc
V
IN
= 17, 28, and 40 V dc,
B.W. = DC to 2MHz
V
IN
=17,28, and 40 V dc
V
IN
= 17, 28, and 40 V dc,
I
out
= 0,
±313,
and
±625mA
V
IN
= 17, 28, and 40 V dc,
I
OUT
= 0,
±313,and ±625
mA
I
OUT
= 0, inhibit (pin 2)
tied to input return (pin 10)
I
OUT
= 0,
inhibit (pin 2) = open
I
OUT
=
±625mA
B.W. = DC to 2MHz
I
OUT
=
±625mA
T
C
= +25°C
Input to output or any pin
to case (except pin 8)
at 500V dc Tc = +25ºC
No effect on dc
performance,
Tc = +25ºC
3
Overload, T
C
= +25°C
Short circuit, T
C
= +25°C
I
OUT
=
±625mA
50% load to/from100%load
No load to/from 50% load
Group A
Subgroups
Device
Types
Limits
Unit
Output voltage
Output current
9, 11
8, 9
V
OUT
I
OUT
V
RIP
P
OUT
VR
LINE
VR
LOAD
I
IN
1
2,3
1,2,3
1,2,3
1,2,3
1
2,3
1,2,3
1,2,3
All
All
All
All
All
All
All
Min
±11.88
±11.70
0.0
Max
±12.12
±12.24
±625
60
V
mA
mVp-p
W
mV
mV
mA
Output ripple voltage
Output power
9
Line
10
Regulation
Load
9
Regulation
Input current
4, 9, 11
15
30
60
120
18
40
Input ripple current
Efficiency
Isolation
Capacitive load
8
I
RIP
E
FF
ISO
1,2,3
1
1
4
1
1
4,5,6
4
5,6
4
5,6
All
All
All
All
All
01
02
03
All
All
225
225
250
-300
-450
-500
-750
80
100
50
mAp-p
%
MΩ
6, 12
C
L
P
D
9
200
6
6
275
245
275
+300
+450
+500
+750
µF
W
kHz
mVpk
Power dissipation
load fault
Switching frequency
F
S
VO
TLOAD
Output response to step
7
transient load changes
4
www.irf.com
AHE28XXD Series
Table II. Electrical Performance Characteristics -
continued
Test
Symbol
Conditions
-55°
≤Tc ≤+125°C
Vin = 28 Vdc ±5%, C
L
= 0
unless otherwise
specified
50% load to/from 100%
load
Group A
Subgroups
Device
Types
Limits
AHE2812D
Unit
Min
Recovery time step
transient load
1, 7
changes
TT
LOAD
4
All
Max
70
µs
Output response
transient step line
5, 12
changes
Recovery time
transient step
1, 5, 12
line changes
Turn on overshoot
2, 9
Turn on delay
9
VO
TLINE
No load to 50% load
50% load to no load
Input step 17 to 40V dc
5,6
4,5,6
4,5,6
4,5,6
All
All
All
100
1500
5
1200
ms
mVpk
TT
LINE
Input step 40 to 17V dc
Input step 17 to 40V dc
4,5,6
4,5,6
All
All
-1500
4
ms
VTon
OS
Ton
D
12
Input step 40 to 17V dc
I
OUT =
0 and
±
625mA
I
OUT
= 0 and
±625mA
4,5,6
4,5,6
4,5,6
4,5,6
All
All
All
All
4
600
10
10
mVpk
ms
ms
Load fault recovery
Tr
LF
Notes to Specifications
1
2
3
4
5
6
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.
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.
An overload is that condition with a load in excess of the rated load but less than that necessary to trigger the short circuit
protection and is the condition of maximum power dissipation.
Total power at both outputs. For operation at 16 V dc input, derate output power by 33 percent.
Input step transition time between 2 and 10 microseconds.
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.
Load step transition time between 2 and 10 microseconds.
Bandwidth guaranteed by design. Tested for 20 KHz to 2MHz.
Tested at each output.
When operating with unbalanced loads, at least 25 percent of the load must be on the positive output to maintain regulation.
Parameter guaranteed by line and load regulation tests.
Parameter shall be tested as part of design characterization and after design or process changes. Thereafter parameters shall be
guaranteed to the limits specified in Table I.
7
8
9
10
11
12
www.irf.com
5