PD-94554B
AHE28XXS SERIES
28V Input, Single Output
HYBRID-HIGH RELIABILITY
DC/DC CONVERTER
Description
The AHE28XXS 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 +5V, +12V and +15V
single 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.
Three standard temperature grades are offered with
screening options. Refer to Part Number section. They
can be provided in a standard plug-in package for PC
mounting or in a flanged package for more severe
environments.
Manufactured in a facility fully qualified to MIL-PRF-
38534, these converters are fabricated utilizing DSCC
qualified processes. For available screening options,
refer to device screening table in the data sheet. Variations
in electrical, mechanical and screening can be
accommodated. Extensive computer simulation using
complex modeling enables rapid design modification
to be provided. Contact IR Santa Clara with specific
requirements.
AHE
Features
n
n
n
n
n
n
n
n
n
n
n
n
n
n
17V to 40VDC Input Range (28VDC Nominal)
5
V, 12V and 15V Outputs Available
Indefinite Short Circuit and Overload Protection
3
17 W/in Power Density
15W and 20W Output Power Models
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 84%
Shutdown from External Signal
Military Screening
325,000 hour MTBF at 85°C (AUC)
Standard Microcircuit Drawings Available
www.irf.com
1
01/08/07
AHE28XXS Series
Specifications
T
CASE
= -55°C to +85°C, V
IN
= +28V
±
5% unless otherwise specified
Absolute Maximum Ratings
Input Voltage
Power Output
1
-0.5V to +50VDC
Internally limited, 17.5W typ. for AHE2805S, 22.5W typ. for AHE2812S and AHE2815S
300°C for 10 seconds
Operating Temperature
Storage Case Temperature
-55°C to +125°C
-65°C to +135°C
AHE2812S
AHE2815S
Soldering Temperature
Temperature Range
1
Parameter
Conditions
-55°C
≤
Tc
≤
+85°C
Vin = 28 Vdc ±5%,C
L
= 0
Unless otherwise specified
Min
AHE2805S
Typ
Max
Min
Typ
Max
Min
Typ
Max
Units
Static Characteristic
OUTPUT
Voltage
Current
Ripple
Accuracy
1
Power
REGULATION
Line
Load
INPUT
4
Voltage Range
Current
Ripple Current
Efficiency
Capacitive Load
Load fault power
4
dissipation
Isolation
Dynamic
Characteristic
Step Load Changes
Output
Transient
Recovery
2
V
IN
=17 to 40 VDC
I
OUT
=0 to Full Load
Full Load, DC to 1MHz
T
CASE
= 25°C, I
OUT
= 0
4.90
0.0
4.95
15
5.00
20
5.00
±
0.5
±0.5
5.10
3000
60
5.05
±
1.0
±1.0
40
18
35
50
11.76
0.0
11.88
20
12.00
30
12.00
±
0.5
±0.5
12.24
1667
60
12.12
±
1.0
±1.0
40
18
35
50
14.70
0.0
14.85
20
15.00
30
15.00
±
0.5
±0.5
15.30
1333
60
15.15
±
1.0
±1.0
40
18
35
50
VDC
mADC
mVp-p
VDC
W
%
V
IN
= 17 to 40 VDC
I
OUT
= to Full Load
17
Inhibited
No Load
Full Load
T
CASE
= +25°C
Half Load to Full Load
No effect on performance
28
8.0
20
17
28
8.0
25
17
28.0
8.0
25
VDC
mADC
mADC
mV p-p
%
µF
80
500
82
79
200
6.0
83
80
200
6.0
84
6.0
100
W
M
Ω
Input to Output @ 500Vdc
100
100
50% Load 100% Load
No Load 50% Load
50% Load No Load
50% Load 100% Load
No Load 50% Load
50% Load No Load
±150
-300
+300
25
500
7.0
±200
-400
+400
25
500
7.0
±200
-400
+400
25
500
7.0
mVpk
mVpk
mVpk
µs
µ
s
msec
mVpk
mVpk
µs
µs
500
14
14
55
58
mVpk
ms
ms
g
Step Line Changes
Output
Transient
2
Recovery
Turn-On
Overshoot Delay
3
Load Fault
4
Recovery
Weight
Input step 17 to 40VDC
Input step 40 to 17VDC
Input step 17 to 40VDC
Input step 40 to 17VDC
VIN = 17 to 40VDC
IOUT = 0 to Full load
VIN = 17 to 40VDC
Standard Package
Flange Package
+180
-600
400
400
0
8.0
8.0
55
58
500
14
14
+180
-600
400
400
300
8.0
8.0
55
58
600
14
14
+180
-600
400
400
300
8.0
8.0
Notes to Specifications
1. Above +85°C case temperature, derate output power linearly to 0 and maximum input voltage linearly to 42V at 115°C case.
2. Recovery time is measured from the initiation of the transient to where V
OUT
has returned to within
±1.0%
of V
OUT
at 50% load.
See typical waveforms.
3. Turn-on delay time measurement is for either an application of power at the input or a signal at the shutdown pin.
4. For operation at 16VDC, derate output power by 33%.
2
www.irf.com
AHE28XXS Series
Specifications
T
CASE
= -55°C to +105°C, V
IN
= +28V
±
5% unless otherwise specified
Absolute Maximum Ratings
Input Voltage
Power Output
5
-0.5V to +50VDC
Internally limited, 17.5W typ. for AHE2805S/ES, 22.5W typ. for AHE2812S/ES and AHE2815S/ES
1
Soldering Temperature 300°C for 10 seconds
Temperature Range
Operating Temperature
Storage Case Temperature
Parameter
Conditions
-55°C
≤
Tc
≤
+105°C
Vin = 28 Vdc ±5%,C
L
= 0
Unless otherwise specified
Min
Static Characteristic
OUTPUT
Voltage
Current
Ripple
Accuracy
Power
1
REGULATION
Line
Load
INPUT
Voltage Range
4
Current
Ripple Current
Efficiency
Capacitive Load
Load fault power
dissipation
4
Isolation
Dynamic
Characteristic
Step Load Changes
Output
Transient
Recovery
2
V
IN
=17 to 40 VDC
I
OUT
=0 to Full Load
Full Load, DC to 1MHz
T
CASE
= 25°C, I
OUT
= 0
4.90
0.0
4.95
15
5.00
20
5.00
±0.5
±0.5
17
28
8.0
20
78
500
82
5.10
3000
60
5.05
±1.0
±1.0
40
18
35
50
17
11.76
0.0
11.88
20
12.00
30
12.00
±0.5
±0.5
28
8.0
25
79
200
6.0
Input to Output @ 500Vdc
100
100
100
MΩ
83
12.24
1667
60
12.12
±1.0
±1.0
40
18
35
50
17
14.70
0.0
14.85
20
15.00
30
15.00
±0.5
±0.5
28
8.0
25
80
200
6.0
84
15.30
1333
60
15.15
±1.0
±1.0
40
18
35
50
VDC
mADC
mVp-p
VDC
W
%
-55°C to +125°C
-65°C to +135°C
AHE2812S/ES
AHE2815S/ES
AHE2805S/ES
Typ
Max
Min
Typ
Max
Min
Typ
Max
Units
V
IN
= 17 to 40 VDC
I
OUT
= 0 to Full Load
Inhibited
No Load
Full Load
T
CASE
= +25°C
Half load to Full load
No effect on performance
VDC
mADC
mADC
mV p-p
%
µF
6.0
W
50% Load 100% Load
No Load 50% Load
50% Load No Load
50% Load 100% Load
No Load 50% Load
50% Load No Load
±150
-300
+300
25
500
7.0
±200
-400
+400
25
500
7.0
±200
-400
+400
25
500
7.0
mVpk
mVpk
mVpk
µs
µs
ms
mVpk
mVpk
µs
µs
750
14
14
mVpk
ms
ms
g
Step Line Changes
Output
Transient
Recovery
2
TURN –ON
Overshoot
Delay
3
Load Fault Recovery
4
Weight
Input step 17 to
Input step 40 to
Input step 17 to
Input step 40 to
40VDC
17VDC
40VDC
17VDC
+180
-600
400
400
0
8.0
8.0
60
65
500
14
14
+180
-600
400
400
300
8.0
8.0
60
65
600
14
14
+180
-600
400
400
300
8.0
8.0
60
65
V
IN
= 17 to 40VDC
I
OUT
= 0 to Full Load
V
IN
= 17 to 40VDC
Standard Package
Flange Package
Notes to Specifications
1.
2.
3.
4.
5.
Above +105°C case temperature, derate output power linearly to 0 at 125°C case.
Recovery time is measured from the initiation of the transient to where V
OUT
has returned to within
±1.0%
of V
OUT
at 50% load.
See typical waveforms.
Turn-on delay time measurement is for either an application of power at the input or a signal at the shutdown pin.
For operation at 16VDC, derate output power by 33%.
Above +85°C case temperature, derate maximum input voltage linearly to 33V at +125°C case.
www.irf.com
3
AHE28XXS Series
Specifications
T
CASE
= -55°C to +105°C, V
IN
= +28V
±
5% unless otherwise specified
Absolute Maximum Ratings
Input Voltage
Power Output
1
-0.5V to +50VDC
Internally limited, 17.5W typ. for AHE2805S/HB & CH, 22.5W typ. for AHE281XS/HB & CH
1
Soldering Temperature 300°C for 10 seconds
Temperature Range
Operating Temperature
Storage Case Temperature
Parameter
Conditions
-55°C
≤
Tc
≤
+125°C
Vin = 28 Vdc ±5%,C
L
= 0
Unless otherwise specified
-55°C to +125°C
-65°C to +135°C
AHE2805S/HB&CH
AHE2812S/HB&CH
AHE2815S/HB&CH
Min
Static Characteristic
OUTPUT
Voltage
Current
Ripple
Accuracy
Power
1
REGULATION
Line
Load
INPUT
Voltage Range
4
Current
Ripple Current
Efficiency
Capacitive Load
Load fault power
dissipation
5
Isolation
Dynamic
Characteristic
Step Load Changes
Output T
C
=25°C
Transient
Recovery
2
V
IN
=17 to 40 VDC
I
OUT
=0 to Full Load
Full Load, DC to 1MHz
T
CASE
= 25°C, I
OUT
= 0
4.90
0.0
4.95
15
Typ
Max
Min
Typ
Max
Min
Typ
Max
Units
5.00
20
5.00
5.10
3000
60
5.05
5.0
11.76
0.0
11.88
20
12.00
30
12.00
12.24
1667
60
12.12
30
14.70
0.0
14.85
20
15.00
30
15.00
15.30
1333
60
15.15
35
VDC
mADC
mVp-p
VDC
W
mV
V
IN
= 17 to 40 VDC
T
CASE
= 25°C
I
OUT
= 0 to Full Load
Inhibited
No Load
Full Load
T
CASE
= +25°C
No effect on performance
Short Circuit T
C
=25°C
Overload T
C
= 25°C
Input to Output @ 500Vdc
10
17
28
8.0
20
82
1000
50
40
18
35
50
50
17
28
8.0
25
83
1000
120
40
18
35
50
50
17
28
8.0
25
84
1000
150
40
18
35
50
VDC
mADC
mADC
mV p-p
%
µF
W
MΩ
80
500
80
200
4.5
6.0
80
200
4.5
6.0
4.5
6.0
100
100
100
50% Load 100% Load
No Load 50% Load
50% Load No Load
50% Load 100% Load
No Load 50% Load
50% Load No Load
Input step 17 to 40VDC
Input step 40 to 17VDC
Input step 17 to 40VDC
Input step 40 to 17VDC
V
IN
= 17 to 40VDC
I
OUT
= 0 to Full Load
V
IN
= 17 to 40VDC
Standard Package
Flange Package
±150
-300
+300
25
100
±300
-500
+500
70
200
5.0
+300
1000
800
800
550
10
10
±200
-400
+400
25
500
±300
-500
+500
70
1500
5.0
+500
-1500
800
800
600
10
10
±200
-400
+400
25
500
±300
-500
+500
70
1500
5.0
+500
-1500
800
800
500
10
10
55
58
mVpk
mVpk
mVpk
µs
µs
ms
mVpk
mVpk
µs
µs
mVpk
ms
ms
g
Step Line Changes
Output T
C
= 25°C
Transient
Recovery
2
TURN –ON
Overshoot
Delay
3
Load Fault Recovery
4
Weight
+180
-600
400
400
0
8.0
8.0
55
58
+180
-600
400
400
300
8.0
8.0
55
58
+180
-600
400
400
300
8.0
8.0
Notes to Specifications
1.
2.
3.
4.
5.
Above +125°C case temperature, derate output power linearly to 0 at 135°C case.
Recovery time is measured from the initiation of the transient to where V
OUT
has returned to within
±1.0%
of V
OUT
at 50% load.
See typical waveforms.
Turn-on delay time measurement is for either an application of power at the input or a signal at the shutdown pin.
For operation at 16VDC, derate output power by 33%.
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.
4
www.irf.com
AHE28XXS Series
Block Diagram
+Input
1
Inhibit
Input
2
Sync
9
Input
Return
10
Drive 1
5 +Vout
EMI
Filter
4
Output
Return
Pulse Width
Modulator
FB
Drive 2
Error
Amp &
Ref
3 V
ADJ
Application Information
Inhibit Function
Connecting the inhibit input (Pin 2) to input common (Pin 10)
will cause the converter to shut down. It is recommended
that the inhibit pin be driven by an open collector device
capable of sinking at least 400µA of current. The open
circuit voltage of the inhibit input is 11.5 ± 1.0VDC.
Device Synchronization
Whenever multiple DC/DC converters are utilized in a
single system, significant low frequency noise may be
generated due to slight difference in the switching
frequencies of the converters (beat frequency noise).
Because of the low frequency nature of this noise
(typically less than 10KHz), it is difficult to filter out and
may interfere with proper operation of sensitive systems
(communications, radar or telemetry). Intenational
Rectifier offers an option, which provides synchronization
of multiple AHE/ATW/ATO type converters, thus
eliminating this type of noise.
EMI Filter
An EMI filter (AFC461), available as an option, will reduce
the input ripple current to levels below the limits imposed by
MIL-STD-461B CEO.
Output Voltage Adjustment (AHE2805 only)
The output voltage of the AHE2805S converter can be
adjusted upward by connecting an appropriate resistor
between Output Adjust (Pin 3) and Output Common
(Pin 4) as shown in Table 1 below.
Table 1 Output adjustment resistor values
Typical Synchronization Connection
+ In
Return
AFC461
or
AFV461
Output
+ In
Case
Return
Return
AHE28xxS
- MSTR
MSTR
Output
Return
Resistance Pin 3 to 4 ( )
None
390K
145K
63K
22K
0
:
Output Voltage Increases (%)
0
+1%
+2%
+3%
+4%
+5%
+ In
Case
System
Bus
Return
AHE28xxD
-SLV
SLV
+Output
Return
-Output
+ In
Case
Return
AHE28xxS
-SLV
SLV
Output
Return
www.irf.com
5
