03/09/10
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HYBRID-HIGH RELIABILITY
DC-DC CONVERTER
AHF28XX SERIES
Description
Features
AHF
28V Input, Single and Dual Output
The proprietary magnetic feedback circuit provides for
an extremely wide bandwidth control loop with a high
phase margin. The closed loop frequency response of
this converter family extends to approximately 50KHz,
resulting in superior line and load transient characteristics.
This feedback method is also inherently temperature
and radiation insensitive. This gives the AHF Series
an important advantage over converters that incorporate
opto-couplers in their design.
The AHF Series of DC-DC converters feature single or
dual outputs over the full military temperature range.
No derating in output power is required, making them
suitable for use in rugged military applications. The
low profile, small outline package is ideally suited to
the tight board space requirements of many industrial
and aerospace applications. Designed for nominal
28Vdc inputs, this family of converters will meet the
requirements of MIL-STD-704D. The basic circuit
utilizes a pulse width modulated, feed-forward topology
at a nominal switching frequency of 550KHz. Input to
output isolation is achieved through the use of
transformers in the forward and feedback circuits.
Extensive computer simulation using complex modeling
enables rapid design modification to be provided.
Contact IR San Jose with specific requirements.
n16V to 40VDC Input Range (28 VDC Nominal)
nSingle and Dual Outputs
n12W Output Power
n22.8W/in3 Power Density
nLow Input / Output Noise
(50mA/60mVp-p max. respectively)
nIndefinite Short Circuit and Overload Protection
nWideband Control Loop for Superior Transient
Characterstics
n No derating for -55°C to +125°C Operation
n Constant Switching Frequency (550KHz Nominal)
nStandard Microcircuit Drawings Available
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 are electrical, mechanical and screening
can be accommodated.
PD-94541D
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AHF28XX Series
Specifications AHF2803R3S
Input voltage -0.5V to +50V
Soldering temperature 300°C for 10 seconds
Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
For Notes to Specifications, refer to page 3
Table I. Electrical Performance Characteristics
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
1 3.26 3.34
2,3 3.23 3.36
Output current1IOUT VIN = 16, 28, and 40Vdc 1,2,3 01 3000 mA
VIN = 16, 28, and 40Vdc,
B.W. = 20 Hz to 2MHz
VIN = 16, 28, and 40Vdc,
Line regulation VRLINE Iout = 0%, 50% and 100% 1,2,3 01 25 mV
rated load
VIN = 16, 28, and 40Vdc,
Load regulation VRLOAD IOUT = 0%, 50% and 100% 1,2,3 01 50 mV
rated load
IOUT = 0, inhibit (pin 1)
tied to input return (pin 7)
IOUT = 0,
inhibit (pin 1) = open
IOUT = 100% rated load
B.W. = 20 Hz to 2.0MHz
172
2,3 70
Input to output or any pin
Isolation ISO to case (except pin 6) 1 01 100 MΩ
at 500Vdc, Tc = +25°C
No effect on dc performance,
Tc = +25°C
Power dissipation Overload 5101 6.0
load fault Short circuit 1,2,3 01 2.0
Switching frequency FSIOUT = 100% rated load 4,5,6 01 500 600 KHz
01 500 µF
PDW
mA
mA p-p
Efficiency EFF IOUT = 100% rated load 01 %
Input ripple current2IRIP 1,2,3
01 V
01 60 mV p-p
Input current 01
12
01
Capacitive load3, 4 CL4
Output voltage VOUT IOUT = 0
Output ripple voltage2VRIP
IIN 1,2,3
1,2,3
Limits
50
30
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AHF28XX Series
Table I. Electrical Performance Characteristics - continued
1. Parameter guaranteed by line and load regulation tests.
2. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
3. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance.
A capacitive 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.
4. 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.
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. Load step transition time between 2.0µs and 10µs.
7. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1.0
percent of VOUT at 50 percent load.
8. Input step transition time between 2.0µs and 10µs.
9. Turn-on delay time measurement is for either a step application of power at the input or the removal of
ground signal from the inhibit pin (pin 1) while power is applied to the input is unlimited.
Notes to Specifications
AHF2803R3S
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
50% to/from 100%
rated load
0% to/from 50%
rated load
50% to/from 100% rated load 4,5,6 70 µs
0% to/from 50% rated load 4,5,6 1200 µs
50% to/from 0% rated load 4,5,6 8.0 ms
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 500 mVpk
rated load 4, 8
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 800 µs
rated load 4, 7, 8
Turn on overshoot VTonOS IOUT = o and 100% rated load 4,5,6 01 600 mVpk
Turn on delay TonDIOUT = o and 100% rated load94,5,6 01 20 ms
Load fault
recovery4, 9
Weight 38 g
01
Output response to
transient step line
changes
VOTLINE 01
Output response to
step transient load
changes6
VOTLOAD
Recovery time step
transient load
changes6, 7
TTLOAD
+300
-500 +500
mVpk
Limits
Recovery time
transient step line
changes
TTLINE 01
4,5,6
4,5,6
01
-300
ms
TrLF 4,5,6 01 20
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AHF28XX Series
Specifications
For Notes to Specifications, refer to page 5
Table II. Electrical Performance Characteristics
AHF2805S
Input voltage -0.5V to +50V
Soldering temperature 300°C for 10 seconds
Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
1 4.95 5.05
2,3 4.90 5.10
Output current1IOUT VIN = 16, 28, and 40Vdc 1,2,3 01 2400 mA
VIN = 16, 28, and 40Vdc,
B.W. = 20 Hz to 2MHz
VIN = 16, 28, and 40Vdc,
Line regulation VRLINE Iout = 0%, 50% and 100% 1,2,3 01 25 mV
rated load
VIN = 16, 28, and 40Vdc,
Load regulation VRLOAD IOUT = 0%, 50% and 100% 1,2,3 01 50 mV
rated load
IOUT = 0, inhibit (pin 1)
tied to input return (pin 7)
IOUT = 0,
inhibit (pin 1) = open
IOUT = 100% rated load
B.W. = 20 Hz to 2.0MHz
176
2,3 74
Input to output or any pin
Isolation ISO to case (except pin 6) 1 01 100 MΩ
at 500Vdc, Tc = +25°C
No effect on dc performance,
Tc = +25°C
Power dissipation Overload 5101 6.0
load fault Short circuit 1,2,3 01 2.0
Switching frequency FSIOUT = 100% rated load 4,5,6 01 500 600 KHz
Limits
50
30
IIN 1,2,3
1,2,3
Output voltage VOUT IOUT = 0
Output ripple voltage2VRIP
Input current 01
12
01
Capacitive load3, 4 CL4
01 V
01 60 mV p-p
mA
mA p-p
Efficiency EFF IOUT = 100% rated load 01 %
Input ripple current2IRIP 1,2,3
01 500 µF
PDW
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AHF28XX Series
Table II. Electrical Performance Characteristics - continued
Notes to Specifications
AHF2805S
1. Parameter guaranteed by line and load regulation tests.
2. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
3. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance.
A capacitive 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.
4. 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.
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. Load step transition time between 2.0µs and 10µs.
7. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1.0
percent of VOUT at 50 percent load.
8. Input step transition time between 2.0µs and 10µs.
9. Turn-on delay time measurement is for either a step application of power at the input or the removal of
ground signal from the inhibit pin (pin 1) while power is applied to the input is unlimited.
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
50% to/from 100%
rated load
0% to/from 50%
rated load
50% to/from 100% rated load 4,5,6 70 µs
0% to/from 50% rated load 4,5,6 1200 µs
50% to/from 0% rated load 4,5,6 8.0 ms
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 500 mVpk
rated load 4, 8
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 800 µs
rated load 4, 7, 8
Turn on overshoot VTonOS IOUT = o and 100% rated load 4,5,6 01 600 mVpk
Turn on delay TonDIOUT = o and 100% rated load94,5,6 01 20 ms
Load fault
recovery4, 9
Weight 38 g
ms
TrLF 4,5,6 01 20
Limits
Recovery time
transient step line
changes
TTLINE 01
4,5,6
4,5,6
01
-300 +300
-500 +500
mVpk
Output response to
step transient load
changes6
VOTLOAD
Recovery time step
transient load
changes6, 7
TTLOAD 01
Output response to
transient step line
changes
VOTLINE 01
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AHF28XX Series
Specifications AHF2812S
Table III. Electrical Performance Characteristics
For Notes to Specifications, refer to page 7
Input voltage -0.5V to +50V
Soldering temperature 300°C for 10 seconds
Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
1 11.88 12.12
2,3 11.76 12.24
Output current1IOUT VIN = 16, 28, and 40Vdc 1,2,3 01 1000 mA
VIN = 16, 28, and 40Vdc,
B.W. = 20 Hz to 2MHz
VIN = 16, 28, and 40Vdc,
Line regulation VRLINE Iout = 0%, 50% and 100% 1,2,3 01 50 mV
rated load
VIN = 16, 28, and 40Vdc,
Load regulation VRLOAD IOUT = 0%, 50% and 100% 1,2,3 01 50 mV
rated load
IOUT = 0, inhibit (pin 1)
tied to input return (pin 7)
IOUT = 0,
inhibit (pin 1) = open
IOUT = 100% rated load
B.W. = 20 Hz to 2.0MHz
178
2,3 75
Input to output or any pin
Isolation ISO to case (except pin 6) 1 01 100 MΩ
at 500Vdc, Tc = +25°C
No effect on dc performance,
Tc = +25°C
Power dissipation Overload 5101 6.0
load fault Short circuit 1,2,3 01 2.0
Switching frequency FSIOUT = 100% rated load 4,5,6 01 500 600 KHz
01 500 µF
PDW
mA
mA p-p
Efficiency EFF IOUT = 100% rated load 01 %
Input ripple current2IRIP 1,2,3
01 V
01 60 mV p-p
Input current 01
12
01
Capacitive load3, 4 CL4
Output voltage VOUT IOUT = 0
Output ripple voltage2VRIP
IIN 1,2,3
1,2,3
Limits
50
50
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AHF28XX Series
Table III. Electrical Performance Characteristics - continued AHF2812S
Notes to Specifications
1. Parameter guaranteed by line and load regulation tests.
2. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
3. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance.
A capacitive 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.
4. 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 II.
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. Load step transition time between 2.0µs and 10µs.
7. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1.0
percent of VOUT at 50 percent load.
8. Input step transition time between 2.0µs and 10µs.
9. 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 1) while power is applied to the input is unlimited.
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
50% to/from 100% 4 -300 +300
rated load 5,6 -450 +450
0% to/from 50% 4 -500 +500
rated load 5,6 -750 +750
50% to/from 100% rated load 4,5,6 100 µs
0% to/from 50% rated load 4,5,6 1500 µs
50% to/from 0% rated load 4,5,6 10 ms
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 1500 mVpk
rated load 4, 8
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 800 µs
rated load 4, 7, 8
Turn on overshoot VTonOS IOUT = o and 100% rated load 4,5,6 01 600 mVpk
Turn on delay TonDIOUT = o and 100% rated load94,5,6 01 20 ms
Load fault
recovery4, 9
Weight 38 g
VOTLINE 01
mVpk
Limits
Recovery time
transient step line
changes
TTLINE 01
01
Output response to
step transient load
changes6
VOTLOAD
Recovery time step
transient load
changes6, 7
TTLOAD 01
Output response to
transient step line
changes
ms
TrLF 4,5,6 01 20
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AHF28XX Series
Specifications
Table IV. Electrical Performance Characteristics
AHF2815S
For Notes to Specifications, refer to page 9
Input voltage -0.5V to +50V
Soldering temperature 300°C for 10 seconds
Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
1 14.85 15.15
2,3 14.70 15.30
Output current1IOUT VIN = 16, 28, and 40Vdc 1,2,3 All 800 mA
VIN = 16, 28, and 40Vdc,
B.W. = 20 Hz to 2MHz
VIN = 16, 28, and 40Vdc,
Line regulation VRLINE Iout = 0%, 50% and 100% All mV
rated load 2,3 ±75
VIN = 16, 28, and 40Vdc,
Load regulation VRLOAD IOUT = 0%, 50% and 100% 1,2,3 All ±150 mV
rated load
IOUT = 0, inhibit (pin 1)
tied to input return (pin 7)
IOUT = 0,
inhibit (pin 1) = open
IOUT = 100% rated load
B.W. = 20 Hz to 2.0MHz
180
2,3 77
Input to output or any pin
Isolation ISO to case (except pin 6) 1 All 100 MΩ
at 500Vdc, Tc = +25°C
No effect on dc performance,
Tc = +25°C
Power dissipation Overload 51All 6.0
load fault Short circuit 1,2,3 All 2.0
01, 04 250 300
Switching frequency FSIOUT = 100% rated load 4,5,6 02, 05 250 270 KHz
03, 06 275 300
Limits
20
50
±35
IIN 1,2,3
1,2,3
1
Output voltage VOUT IOUT = 0
Output ripple voltage2VRIP
Input current All
18
All
Capacitive load3, 4 CL4
All V
All 50 mV p-p
mA
mA p-p
Efficiency EFF IOUT = 100% rated load All %
Input ripple current2IRIP 1,2,3
All 200 µF
PDW
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AHF28XX Series
Table IV. Electrical Performance Characteristics - continued AHF2815S
Notes to Specifications
1. Parameter guaranteed by line and load regulation tests.
2. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
3. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance.
A capacitive 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.
4. 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 III.
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. Load step transition time between 2.0µs and 10µs.
7. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1.0
percent of VOUT at 50 percent load.
8. Input step transition time between 2.0µs and 10µs.
9. 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 is unlimited.
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
50% to/from 100%
rated load
0% to/from 50%
rated load
4100
5,6 200
45.0
5,6 10
Input step 16V to/from 04
40Vdc, IOUT = 100% 4,5,6 05 -1000 +1000 mVpk
rated load 4, 8 06
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 500 µs
rated load 4, 7, 8
Turn on overshoot VTonOS IOUT = o and 100% rated load 4,5,6 All 750 mVpk
Turn on delay TonDIOUT = o and 100% rated load94,5,6 All 12 ms
Load fault
recovery4, 9
Weight 38 g
mVpk
4,5,6
-800 +800
-1000 +750
Output response to
step transient load
changes6
VOTLOAD
ms
TrLF 4,5,6 All 12
µs
ms
4,5,6
0% to/from 50% rated load
All
TTLOAD
Output response to
transient step line
changes
Recovery time
transient step line
changes
TTLINE
VOTLINE
Limits
01
All
Recovery time step
transient load
changes6, 7
50% to/from 100% rated load
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AHF28XX Series
Specifications AHF2805D
Table V. Electrical Performance Characteristics
For Notes to Specifications, refer to page 11
Input voltage -0.5V to +50V
Soldering temperature 300°C for 10 seconds
Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
1 ±4.95 ±5.05
2,3 ±4.90 ±5.10
VIN = 16, 28, and 40Vdc
each output
VIN = 16, 28, and 40Vdc,
B.W. = 20 Hz to 2MHz
VIN = 16, 28, and 40Vdc,
Line regulation4VRLINE Iout = 0%, 50% and 100% 1,2,3 01 30 mV
rated load
VIN = 16, 28, and 40Vdc,
Load regulation4VRLOAD IOUT = 0%, 50% and 100% 1,2,3 01 30 mV
rated load
Cross regulation5VRCROSS 10% to 90% load changes 1,2,3 01 ±10 %
IOUT = 0, inhibit (pin 1)
tied to input return (pin 7)
IOUT = 0,
inhibit (pin 1) = open
IOUT = 100% rated load
B.W. = 20 Hz to 2.0MHz
IOUT = 100% rated load, 1,3 75
Tc = +25°C, 272
Input to output or any pin
Isolation ISO to case (except pin 6) 1 01 100 MΩ
at 500Vdc, Tc = +25°C
No effect on dc performance,
Tc = +25°C,
total for both outputs
Power dissipation Overload, Tc = +25°C 6.0
load fault Short circuit, Tc = +25°C 2.0
Switching frequency FSIOUT = 100% rated load 4,5,6 01 500 600 KHz
mA
Capacitive load6, 7
011,2,3
Input current IIN 1,2,3
PDW
µF200014
CL
mA p-p
Efficiency4EFF 01 %
Input ripple current3, 4 IRIP 1,2,3
V
01 60 mV p-p
A0.12 1.0801
01
12
01 50
60
Output voltage VOUT IOUT = 0
Output ripple voltage3VRIP
Output current1, 2 IOUT
1,2,3
Limits
01
1,2,3
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AHF28XX Series
Table V. Electrical Performance Characteristics - continued AHF2805D
Notes to Specifications
1. Parameter guaranteed by line load and cross regulation tests.
2. Up to 90 percent of full power is available from either output provided the total output does not exceed 12W.
3. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
4. Load current split equally between +VOUT and –VOUT.
5. 1.2 watt load on output under test, 1.2W to 10.8W load change on other output.
6. 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.
7. 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 IV.
8. 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.
9. Load step transition time between 2.0µs and 10µs.
10. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1.0
percent of VOUT at 50 percent load.
11. Input step transition time between 2.0µs and 10µs.
12. 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 1) while power is applied to the input.
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
50% to/from 100%
rated load
0% to/from 50%
rated load
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 01 -400 +400 mVpk
rated load
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 1200 µs
rated load
Turn on overshoot4VTonOS IOUT = o and 100% rated load 4,5,6 01 600 mVpk
Turn on delay TonDIOUT = o and 100% rated load94,5,6 01 25 ms
Load fault
recovery4, 9
Weight 38 g
Limits
70
VOTLOAD
Recovery time
transient step line
changes4, 7, 10, 11
TTLINE
VOTLINE
01
01
Recovery time step
transient load
changes4, 9,10
50% to/from 100% rated load
0% to/from 50% rated load
01
TTLOAD
Output response to
transient step line
changes 4, 7, 11
4,5,6
Output response to
step transient load
changes4, 9
ms
TrLF 4,5,6 01 25
µs
4,5,6
4,5,6
-400 +400
-800 +800
mVpk
4,5,6
100
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AHF28XX Series
Specifications AHF2812D
Table VI. Electrical Performance Characteristics
For Notes to Specifications, refer to page 13
Input voltage -0.5V to +50V
Soldering temperature 300°C for 10 seconds
Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
1 ±11.88 ±12.12
2,3 ±11.76 ±12.24
VIN = 16, 28, and 40Vdc
each output
VIN = 16, 28, and 40Vdc,
B.W. = 20 Hz to 2MHz
VIN = 16, 28, and 40Vdc,
Line regulation4VRLINE Iout = 0%, 50% and 100% 1,2,3 01 30 mV
rated load
VIN = 16, 28, and 40Vdc,
Load regulation4VRLOAD IOUT = 0%, 50% and 100% 1,2,3 01 30 mV
rated load
Cross regulation5VRCROSS 10% to 90% load changes 1,2,3 01 3.0 %
IOUT = 0, inhibit (pin 1)
tied to input return (pin 7)
IOUT = 0,
inhibit (pin 1) = open
IOUT = 100% rated load
B.W. = 20 Hz to 2.0MHz
IOUT = 100% rated load, 1,3 77
Tc = +25°C 274
Input to output or any pin
Isolation ISO to case (except pin 6) 1 01 100 MΩ
at 500Vdc, Tc = +25°C
No effect on dc performance,
Tc = +25°C,
total for both outputs
Power dissipation Overload, Tc = +25°C 6.0
load fault Short circuit, Tc = +25°C 2.0
Switching frequency FSIOUT = 100% rated load 4,5,6 01 500 600 KHz
1,2,3
Limits
01
1,2,3
Output voltage VOUT IOUT = 0
Output ripple voltage3VRIP
Output current1, 2 IOUT
01
12
01 50
60
V
01 60 mV p-p
mA100 90001
mA p-p
Efficiency4EFF 01 %
Input ripple current3, 4 IRIP 1,2,3
200014
CL
mA
Capacitive load6, 7
011,2,3
Input current IIN 1,2,3
PDW
µF
www.irf.com 13
AHF28XX Series
Table VI. Electrical Performance Characteristics - continued AHF2812D
Notes to Specifications
1. Parameter guaranteed by line load and cross regulation tests.
2. Up to 90 percent of full power is available from either output provided the total output does not exceed 12W.
3. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
4. Load current split equally between +VOUT and –VOUT.
5. 1.2 watt load on output under test, 1.2W to 10.8W load change on other output.
6. Capacitive load may be any value from 0 to the maximum limit without compromising dc performance.
A capacitive oad 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.
7. 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 V.
8. 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.
9. Load step transition time between 2.0µs and 10µs.
10. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1.0
percent of VOUT at 50 percent load.
11. Input step transition time between 2.0µs and 10µs.
12. 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 1) while power is applied to the input.
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
50% to/from 100%
rated load
0% to/from 50%
rated load
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 01 -750 +750 mVpk
rated load
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 1200 µs
rated load
Turn on overshoot4VTonOS IOUT = o and 100% rated load 4,5,6 01 600 mVpk
Turn on delay TonDIOUT = o and 100% rated load94,5,6 01 25 ms
Load fault
recovery4, 9
Weight 38 g
µs
4,5,6
4,5,6
-200 +200
-800 +800
mVpk
4,5,6
1000
ms
TrLF 4,5,6 01 25
01
01
Recovery time step
transient load
changes4, 9,10
50% to/from 100% rated load
0% to/from 50% rated load
01
TTLOAD
Output response to
transient step line
changes 4, 7, 11
4,5,6
Output response to
step transient load
changes4, 9
VOTLOAD
Recovery time
transient step line
changes4, 7, 10, 11
TTLINE
VOTLINE
Limits
70
14 www.irf.com
AHF28XX Series
Specifications AHF2815D
Table VII. Electrical Performance Characteristics
For Notes to Specifications, refer to page 15
Input voltage -0.5V to +50V
Soldering temperature 300°C for 10 seconds
Operating case temperature -55°C to +125°C
Storage case temperature -65°C to +135°C
Absolute Maximum Ratings
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
1 ±14.85 ±15.15
2,3 ±14.70 ±15.30
VIN = 16, 28, and 40Vdc
each output
VIN = 16, 28, and 40Vdc,
B.W. = 20 Hz to 2MHz
VIN = 16, 28, and 40Vdc,
Line regulation4VRLINE Iout = 0%, 50% and 100% 1,2,3 01 35 mV
rated load
VIN = 16, 28, and 40Vdc,
Load regulation4VRLOAD IOUT = 0%, 50% and 100% 1,2,3 01 35 mV
rated load
Cross regulation5VRCROSS 10% to 90% load changes 1,2,3 01 3.0 %
IOUT = 0, inhibit (pin 1)
tied to input return (pin 7)
IOUT = 0,
inhibit (pin 1) = open
IOUT = 100% rated load
B.W. = 20 Hz to 2.0MHz
IOUT = 100% rated load, 1,3 78
Tc = +25°C 275
Input to output or any pin
Isolation ISO to case (except pin 6) 1 01 100 MΩ
at 500Vdc, Tc = +25°C
No effect on dc performance,
Tc = +25°C,
total for both outputs
Power dissipation Overload, Tc = +25°C 6.0
load fault Short circuit, Tc = +25°C 2.5
Switching frequency4FSIOUT = 100% rated load 4,5,6 01 500 600 KHz
1,2,3
Limits
01
1,2,3
Output voltage VOUT IOUT = 0
Output ripple voltage3VRIP
Output current1, 2 IOUT
01
12
01 50
55
V
01 60 mV p-p
mA80 72001
mA p-p
Efficiency4EFF 01 %
Input ripple current3, 4 IRIP 1,2,3
200014
CL
mA
Capacitive load6, 7
011,2,3
Input current IIN 1,2,3
PDW
µF
www.irf.com 15
AHF28XX Series
1. Parameter guaranteed by line load and cross regulation tests.
2. Up to 90 percent of full power is available from either output provided the total output does not exceed 12W.
3. Bandwidth guaranteed by design. Tested for 20KHz to 2.0MHz.
4. Load current split equally between +VOUT and –VOUT.
5. 1.2 watt load on output under test, 1.2W to 10.8W load change on other output.
6. 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.
7. 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 VI.
8. 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.
9. Load step transition time between 2.0µs and 10µs.
10. Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1.0
percent of VOUT at 50 percent load.
11. Input step transition time between 2.0µs and 10µs.
12. 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 1) while power is applied to the input.
Table VII. Electrical Performance Characteristics - continued AHF2815D
Notes to Specifications
Test Symbol Conditions Group A Device Unit
-55°C ≤ Tc ≤ +125°C Subgroups Types
Vin = 28Vdc ±5%, CL = 0
Unless otherwise specified Min Max
50% to/from 100%
rated load
0% to/from 50%
rated load
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 01 -750 +750 mVpk
rated load
Input step 16V to/from
40Vdc, IOUT = 100% 4,5,6 1200 µs
rated load
Turn on overshoot4VTonOS IOUT = o and 100% rated load 4,5,6 01 750 mVpk
Turn on delay TonDIOUT = o and 100% rated load94,5,6 01 25 ms
Load fault
recovery4, 9
Weight 38 g
Limits
70
VOTLOAD
Recovery time
transient step line
changes4, 7, 10, 11
TTLINE
VOTLINE
01
01
Recovery time step
transient load
changes4, 9,10
50% to/from 100% rated load
0% to/from 50% rated load
01
TTLOAD
Output response to
transient step line
changes 4, 7, 11
4,5,6
Output response to
step transient load
changes4, 9
ms
TrLF 4,5,6 01 25
µs
4,5,6
4,5,6
-200 +200
-800 +800
mVpk
4,5,6
500
16 www.irf.com
AHF28XX Series
Application Information
Connecting the enable input (Pin 1) to input common (Pin 7)
will cause the converter to shut down. It is recommended
that the enable pin be driven by an open collector device
capable of sinking at least 400µA of current. The open
circuit voltage of the enable input is 15 ± 1.0VDC. If the
inhibit function is not used, this input can be left unconnected
because it is internally pulled-up.
Thermal Management
Assuming that there is no forced air flow, the package
temperature rise above ambient (∆T) may be calculated
using the following expression:
where A = the effective surface area in square inches
(including heat sink if used), P = power dissipation in watts.
The total surface area of the AHF package is 4.9 square
inches. If a worse case full load efficiency of 78% is assumed,
then the case temperature rise can be calculated as follows:
Hence, if TAMBIENT = +25°C, the DC/DC converter case
temperature will be approximately 100°C if no heat sink
or air flow is provided.
Inhibit Function (Enable)
∆T ≈ 80 A –0.7p 0.85 (°C)
W
Eff
PP OUT 4.31
78.0
1
121
1=
⎥
⎦
⎤
⎢
⎣
⎡−=
⎥
⎦
⎤
⎢
⎣
⎡−=
∆T = 80 (4.9)-0.7 (3.4)0.85 = 74°C
To calculate the heat sink area required to maintain a
specific case temperature rise, the above equation may
be manipulated as follows:
PKG
Α−
⎥
⎦
⎤
⎢
⎣
⎡
Ρ
∆Τ −43.1
85.0
80
A HEAT SINK =
As an example, if a maximum case temperature rise of
50°C rise above ambient is desired, then the required
effective heat sink area is:
2
43.1
85.0 .75.39.4
)4.3(80
50 in
HEATSINK =−
⎥
⎦
⎤
⎢
⎣
⎡
=Α
−
Standard Microcircuit Drawing Equivalence Table
Standard Microcircuit Vendor Cage IR Standard
Drawing Number Code Part Number
5962-91600 52467 AHF2805S
5962-94568 52467 AHF2812S
5962-94563 52467 AHF2815S
5962-05205 52467 AHF2805D
5962-92111 52467 AHF2812D
5962-92351 52467 AHF2815D
www.irf.com 17
AHF28XX Series
( Single Output ) Block Diagram
( Dual Output ) Block Diagram
2
3
+Vout
Output
Return
Pulse Width
Modulator
Primary
Housekeeping
Supply
EMI
Filter
Under-Voltage
Detector
8
7
+Input
Enable Input
Input Return
Error
Amp &
Ref
FB
CS
Drive
4-Vout
6
Case
1
4
3
+Vout
Output
Return
Pulse Width
Modulator
Primary
Housekeeping
Supply
EMI
Filter
Under-Voltage
Detector
8
1
7
+Input
Enable Input
Input Return
Error
Amp &
Ref
FB
CS
Drive
6
Case
18 www.irf.com
AHF28XX Series
Pin Designation
Mechanical Outlines
1.450
(36.83)
0.260
(6.600)
0.030 dia., 8 pins
(0.760)
0.800
(20.32)
4
7
5
8
6
1
2
3
1.120
(28.45)
0.090 R Typ
(2.290)
0.330
(8.380)
MAX
1.105
(28.07)
0.905
(22.99)
0.705
(17.91)
0.505
(12.83)
0.205
(5.21)
Non-Flanged
Flanged
Pin # Single Output Dual Output
1 Enable Input Enable Input
2 NC + Output
3 Output Return Output Return
4 + Output - Output
5NC NC
6 Case Case
7 Input Return Input Return
8 +Input +Input
www.irf.com 19
AHF28XX Series
Part Numbering
WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, Tel: (310) 252-7105
IR SAN JOSE: 2520Junction Avenue, San Jose, California 95134, Tel: (408) 434-5000
Visit us at www.irf.com for sales contact information.
Data and specifications subject to change without notice. 03/2010
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
d
HB CH
Temperature Range -20°C to +85°C -55°C to +125°C
e
-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
c
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
d
-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
c
Yes Yes Yes
N/A N/A2023 N/A N/A
AHF 28 05 S F /CH
Model
Input Voltage
Nominal
28 = 28V
Output Voltage
Single – 03R3 = 3.3V
05 = 5V
12 =12V
15 =15V
Dual – 05 = ±5V
12 = ±12V
15 = ±15V
Output
S = Single
D = Dual
Package Style
F = Flange
Blank = Non-Flanged
Screening Level
(Please refer to Screening Table)
No Suffix, ES, HB, CH