01/12/07
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HYBRID-HIGH RELIABILITY
DC/DC CONVERTER
ATO28XXT SERIES
Description
16V to 40VDC Input Range (28VDC Nominal)
5V, ±12V or 5V, ±15V Outputs Available
Indefinite Short Circuit and Overload Protection
15W 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 81%
Shutdown from External Signal
200,000 Hour MTBF at 85°C
Standard Microcircuit Drawings Available
Features
ATO
28V Input, Triple Output
Three standard temperature grades are offered. Refer
to Part Numbering section. They are 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 modest design
modifications to be accommodated. Contact IR Santa
Clara with specific requirements.
The ATO28XXT Series of DC/DC converters feature
high power density and an extended temperature range
for use in military and industrial applications. Designed
to the nominal input requirements of MIL-STD-704D,
these devices have nominal 28VDC inputs with +5V
and ±12V or +5V and ±15V triple 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.
PD - 94582A
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ATO28XXT Series
Specifications
TCASE = -55°C to +85°C, VIN = +28V ± 5% unless otherwise specified
Notes to Specifications
1. Tested at each output.
2. Parameter guaranteed by line and load regulation tests.
3. At least 20 percent of the total output power should be taken from the (+5V) main output.
4. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
5. 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.
6. Above 85°C case temperature, derate output power linearly to 0 at 115°C case.
Input voltage -0.5V to +50VDC
Power Output Internally limited, 17.5W typical
Soldering temperature 300°C for 10 seconds
Tem
p
erature Ran
g
e6 Operating case temperature -55°C to +115°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
ATO2812T
ATO2815T
TEST
SYMBOL
Condition
-55°C ≤ TC ≤ +85°C, VIN = 28 VDC ±5%, CL=0
unless otherwise specified Min Max Min Max Units
STATIC
CHARACTERISTICS
OUTPUT
Voltage 1 V
OUT I
OUT = 0 (main)
IOUT = 0 (dual)1
TC = 25°C
Over Temp
TC = 25°C
Over Temp
4.95
4.90
±11.88
±11.76
5.05
5.10
±12.12
±12.24
4.95
4.90
±14.85
±14.70
5.05
5.10
±15.15
±15.30
V
V
V
V
Current 1,2,3 I
OUT V
IN = 16, 28, and 40 VDC (main) 0.0 2000 0.0 2000 mA
VIN = 16, 28, and 40 VDC (dual)1
VIN = 16, 28, and 40 VDC (dual)
0.0
±208
80
0.0 ±167
80
mA
mVp-p
Ripple Voltage 1,4 V
RIP BW = DC to 2 MHz (main)
VIN = 16, 28, and 40 VDC
BW = DC to 2 MHz (dual))
40
40
mVp-p
Power 1,2,3 P
OUT V
IN = 16, 28, and 40 VDC (main)
(+dual)
(-dual)
(total)
10
2.5
2.5
15
10
2.5
2.5
15
W
W
W
W
REGULATION
Line 1,3
Load 1,3
VRLINE
VRLOAD
VIN = 16, 28, and 40 VDC
IOUT = 0, 1000, 2000mA (main)
VIN = 16, 28, and 40 VDC (dual)
IOUT = 0, ±84, ±167mA (dual)
VIN = 16, 28, and 40 VDC
IOUT = 0, 1000, 2000mA (main)
VIN = 16, 28, and 40 VDC
IOUT = 0, ±84, ±167mA (dual)
TC = 25°C
Over Temp
25
±30
±60
50
±60
25
±35
±75
50
±75
mV
INPUT
Current
Ripple Current 4
IIN
IRIP
IOUT = 0, Inhibit (pin 8)
Tied to input return (pin 10)
IOUT = 0, inhibit (pin 2) = open
IOUT = 2000 mA (main)
IOUT = ±167mA (dual)
BW = DC to 2MHz
15
40
50
15
40
50
mA
mA
mAp-p
EFFICIENCY EFF I
OUT = 2000mA (main)
IOUT = ±167mA (dual)
TC = 25°C 76 76 %
ISOLATION ISO Input to output or any pin to
case (except pin 7) at 500 VDC
TC = 25°C 100 100
MΩ
Load Fault
Power Dissipation 3
PD Overload
Short Circuit
TC = 25°C 8.0
6.0
8.0
6.0
W
Switching Frequency FS I
OUT = 2000mA (main)
IOUT = ±167mA (dual)
225 275 225 275 KHz
Inhibit Open Circuit
Voltage
VOI 9.0 13 9.0 13 V
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ATO28XXT Series
TCASE = -55°C to +105°C, VIN = +28V ± 5% unless otherwise specified
Specifications
1. Tested at each output.
2. Parameter guaranteed by line and load regulation tests.
3. At least 20 percent of the total output power should be taken from the (+5V) main output.
4. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
5. 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.
6. Above 105°C case temperature, derate output power linearly to 0 at 125°C case
Notes to Specifications
Input voltage -0.5V to +50VDC
Power Output Internally limited, 17.5W typical
Soldering temperature 300°C for 10 seconds
Tem
p
erature Ran
g
e6 Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
ATO2812T/ES
ATO2815T/ES
TEST
SYMBOL
Condition
-55°C ≤ TC ≤ +105°C, VIN = 28 VDC ±5%, CL=0
unless otherwise specified
Min Max Min Max Units
STATIC
CHARACTERISTICS
OUTPUT
Voltage 1 V
OUT I
OUT = 0 (main)
IOUT = 0 (dual)1
TC = 25°C
Over Temp
TC = 25°C
Over Temp
4.95
4.90
±11.88
±11.76
5.05
5.10
±12.12
±12.24
4.95
4.90
±14.85
±14.70
5.05
5.10
±15.15
±15.30
V
V
V
V
Current 1,2,3 I
OUT V
IN = 16, 28, and 40 VDC (main) 0.0 2000 0.0 2000 mA
Ripple Voltage 1,4
VRIP
VIN = 16, 28, and 40 VDC (dual)1
VIN = 16, 28, and 40 VDC
0.0
±208
80
0.0 ±167
80
mA
mVp-p
BW = DC to 2 MHz (main)
VIN = 16, 28, and 40 VDC
BW = DC to 2 MHz (dual))
40
40
mVp-p
Power 1,2,3 P
OUT V
IN = 16, 28, and 40 VDC (main)
(+dual)
(-d ual)
(total)
10
2.5
2.5
15
10
2.5
2.5
15
W
W
W
W
REGULATION
Line 1,3
Load 1,3
VRLINE
VRLOAD
VIN = 16, 28, and 40 VDC
IOUT = 0, 1000, 2000mA (main)
VIN = 16, 28, and 40 VDC (dual)
IOUT = 0, ±84, ±167mA (dual)
VIN = 16, 28, and 40 VDC
IOUT = 0, 1000, 2000mA (main)
VIN = 16, 28, and 40 VDC
IOUT = 0, ±84, ±167mA (dual)
TC = 25°C
Over Temp
25
±30
±60
50
±60
25
±35
±75
50
±75
mV
INPUT
Current
Ripple Current 4
IIN
IRIP
IOUT = 0, Inhibit (pin 8)
Tied to input return (pin 10)
IOUT = 0, inhibit (pin 2) = open
IOUT = 2000 mA (main)
IOUT = ±167mA (dual)
BW = DC to 2MHz
15
40
50
15
40
50
mA
mA
mAp-p
EFFICIENCY EFF I
OUT = 2000mA (main)
IOUT = ±167mA (dual)
TC = ±25°C
TC = 25°C 76 76 %
ISOLATION ISO Input to output or any pin to
case (except pin 7) at 500 VDC
TC = 25°C 100 100 MΩ
Load Fault
Power Dissipation 3
PD
Overload, TC = +25°C5
Short Circuit, TC = +25°C
TC = 25°C
8.0
6.0
8.0
6.0
W
Switching Frequency
FS
IOUT = 2000mA (main)
IOUT = ±167mA (dual)
225
275
225
275
KHz
Inhibit Open Circuit
Voltage
VOI 9.0 13 9.0 13 V
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ATO28XXT Series
TCASE = -55°C to +125°C, VIN = +28V ± 5% unless otherwise specified
Specifications
Notes to Specifications
1. Tested at each output.
2. Parameter guaranteed by line and load regulation tests.
3. At least 20 percent of the total output power should be taken from the (+5V) main output.
4. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
5. 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.
6. Above 125°C case temperature, derate output power linearly to 0 at 135°C case
Input voltage -0.5V to +50VDC
Power Output Internally limited, 17.5W typical
Soldering temperature 300°C for 10 seconds
Tem
p
erature Ran
g
e6 Operating case temperature -55°C to +135°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
TEST
SYMBOL
Condition
-55°C ≤ TC ≤+125°C, VIN = 28 VDC ±5%, CL=0
unless otherwise specified
ATO2812T/HB
ATO2815T/HB
Min Max Min Max Units
STATIC
CHARACTERISTICS
OUTPUT
Voltage 1 V
OUT I
OUT = 0 (main)
IOUT = 0 (dual)1
TC = 25°C
Over Temp
TC = 25°C
Over Temp
4.95
4.90
±11.88
±11.76
5.05
5.10
±12.12
±12.24
4.95
4.90
±14.85
±14.70
5.05
5.10
±15.15
±15.30
V
V
V
V
Current 1,2,3 I
OUT V
IN = 16, 28, and 40 VDC (main) 0.0 2000 0.0 2000 mA
Ripple Voltage 1,4
VRIP
VIN = 16, 28, and 40 VDC (dual)1
VIN = 16, 28, and 40 VDC
0.0
±208
80
0.0 ±167
80
mA
mVp-p
BW = DC to 2 MHz (main)
VIN = 16, 28, and 40 VDC
BW = DC to 2 MHz (dual))
40
40
mVp-p
Power 1,2,3 P
OUT V
IN = 16, 28, and 40 VDC (main)
(+dual)
(-dual)
(total)
10
2.5
2.5
15
10
2.5
2.5
15
W
W
W
W
REGULATION
Line 1,3
Load 1,3
VRLINE
VRLOAD
VIN = 16, 28, and 40 VDC
IOUT = 0, 1000, 2000mA (main)
VIN = 16, 28, and 40 VDC (dual)
IOUT = 0, ±84, ±167mA (dual)
VIN = 16, 28, and 40 VDC
IOUT = 0, 1000, 2000mA (main)
VIN = 16, 28, and 40 VDC
IOUT = 0, ±84, ±167mA (dual)
TC = 25°C
Over Temp
25
±30
±60
50
±60
25
±35
±75
50
±75
mV
INPUT
Current
Ripple Current 4
IIN
IRIP
IOUT = 0, Inhibit (pin 8)
Tied to input return (pin 10)
IOUT = 0, inhibit (pin 2) = open
IOUT = 2000 mA (main)
IOUT = ±167mA (dual)
BW = DC to 2MHz
15
40
50
15
40
50
mA
mA
mAp-p
EFFICIENCY EFF I
OUT = 2000mA (main)
IOUT = ±167mA (dual)
TC = ±25°C
TC = 25°C 76 76 %
ISOLATION ISO Input to output or any pin to
case (except pin 7) at 500 VDC
TC = 25°C 100 100 MΩ
Load Fault
Power Dissipation 3
PD
Overload, TC = +25°C5
Short Circuit, TC = +25°C
TC = 25°C
8.0
6.0
8.0
6.0
W
Switching Frequency
FS
IOUT = 2000mA (main)
IOUT = ±167mA (dual)
225
275
225
275
KHz
Inhibit Open Circuit
Voltage
VOI 9.0 13 9.0 13 V
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ATO28XXT Series
Block Diagram
5+ Dual Vout
Output Return
Pulse
Width
Modulator
EMI
Filter
1
8
10
+Input
Enable
Input
Input
Return
FB
Drive 1
Drive 2
Error Amp
& Reference
4- Dual Vout
Regulator
+5V out
3
2
Standard Microcircuit Drawing Equivalence Table
Standard Microcircuit Vendor Cage IR Standard
Drawing Number Code Part Number
5962-90954 52467 ATO2815T
5962-91602 52467 ATO2812T
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ATO28XXT Series
Pin Designation
Mechanical Outlines
Flanged
Non-Flanged
2.70
0
Max
2.360
1.350
Max
1.95
0.500
Max
0.05
0.040 D X
0.26 L Pins
4 X 0.400
=1.600
1.950
Max
0.500
Max
1.350
Max
610987
123 54
1.000
Pin # Designation
1 + Input
2 +5V Output
3 Output Return
4 - Dual Output
5 + Dual Output
6NC
7 Case Ground
8 Enable Input
9NC
10 Input Return
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ATO28XXT Series
Part Numbering
WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, Tel: (310) 252-7105
IR SANTA CLARA: 2270 Martin Av., Santa Clara, California 95050, Tel: (408) 727-0500
Visit us at www.irf.com for sales contact information.
Data and specifications subject to change without notice. 01/2007
Notes:
Best commercial practice
Sample tests at low and high temperatures
-55°C to +105°C for AHE, ATO, ATW
Device Screening
Requirement MIL-STD-883 Method No Suffix ES HB CH
Temperature Range -20°C to +85°C -55°C to +125°C -55°C to +125°C -55°C to +125°C
Element Evaluation MIL-PRF-38534 N/A N/A N/A Class H
Non-Destructive
Bond Pull
Internal Visual 2017 Yes Yes Yes
Temperature Cycle 1010 N/A Cond B Cond C Cond C
Constant Acceleration 2001, Y1 Axis N/A 500 Gs 3000 Gs 3000 Gs
PIND 2020 N/A N/A N/A N/A
Burn-In 1015 N/A 48 hrs@hi temp 160 hrs@125°C 160 hrs@125°C
Final Electrical MIL-PRF-38534 25°C 25°C -55°C, +25°C, -55°C, +25°C,
( Group A ) & Specification +125°C +125°C
PDA MIL-PRF-38534 N/A N/A N/A 10%
Seal, Fine and Gross 1014 Cond A Cond A, C Cond A, C Cond A, C
Radiographic 2012 N/A N/A N/A N/A
External Visual 2009 Yes Yes Yes
N/A N/A2023 N/A N/A
ATO 28 15 T F /CH
Model
Input Voltage
Nominal
28 = 28V
Output Voltage
12 = 5V ±12V
15 = 5V ±15V
Output
T = Triple
Package Style
F = Flange
Blank = Non-Flanged
Screening Level
(Please refer to Screening Table)
No Suffix, ES, HB, CH
