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AHF2800 Series
DESCRIPTION
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 550 KHz. Input to output isolation is achieved through the use of transformers in the forward and feedback circuits. 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 50 kHz, 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. These converters are manufactured in a facility certified to MIL-PRF-38534. All processes used to manufacture these converters have been qualified to enable Lambda Advanced Analog to deliver compliant devices. Four screening grades are available to satisfy a wide range of requirements. The CH grade converters are fully compliant to MIL-PRF-38534 class H. The HB grade converters are processed to full MIL-PRF-38534 screening but do not have class H element evaluation as required by MIL-PRF-38534. Two grades are fully tested and operate over the full military temperature range without derating of output power. Industrial and commercial grades are also available. Variations in electrical, mechanical and screening can be accommodated. Extensive computer simulation using complex modeling enables rapid design modification to be provided. Contact Lambda Advanced Analog with specific requirements.
Hybrid - High Reliability DC/DC Converters
FEATURES
s 16 - 40 VDC input range s s s s s s s s
(28 VDC nominal) Single and dual outputs 12 watts output power 22.8 W/in3 power density Low input/output noise (50 mA/60 mV p-p max. respectively) Indefinite short circuit and overload protection Wideband control loop for superior transient characteristics No derating for -55C to +125C operation Constant switching frequency (550 kHz nominal)
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Input Voltage Soldering Temperature Case Temperature -0.5V to 50V 300C for 10 seconds Operating-55C to +125C Storage -65C to +135C
AHF2812S
TABLE II. Electrical Performance Characteristics
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A subgroups Device types Limits Unit
Min Output voltage VOUT IOUT = 0 1 01 11.88
Max 12.12 V
2,3 Output current 1/ Output ripple voltage 2/ Line regulation Load regulation Input current IOUT VRIP VRLINE VIN = 16, 28, and 40 V dc, VIN = 16, 28, and 40 V dc, B.W. = 20 Hz to 2 MHz VIN = 16, 28, and 40 V dc, IOUT = 0,500, and 1000 mA VIN = 16, 28, and 40 V dc, IOUT = 0, 500, and 1000 mA IOUT = 0, inhibit (pin 1) tied to input return (pin 7) IOUT = 0, inhibit (pin 1) = open Input ripple current 2/ IRIP IOUT = 1000 mA, B.W. = 20 Hz to 2 MHz 1,2,3 01 1,2,3 1,2,3 1,2,3 01 01 01
11.76
12.24 1000 60 50 mA mV p-p mV
VRLOAD
1,2,3
01
50
mV
IIN
1,2,3
01
12
mA
50
50
mA p-p
Efficiency
EFF
IOUT = 1000 mA,
1 2,3
01
78 75
%
Isolation
ISO
Input to output or any pin to case (except pin 6) at 500 V dc, TC = +25C No effect on dc performance, TC = +25C Overload 5/ Short circuit
1
01
100
M
Capacitive load 3/ 4/ Power dissipation load fault
CL PD
4 1 1,2,3 4,5,6
01 01 01 01 500
200 6 2 600
F W
Switching frequency
FS
IOUT = 1000 mA
kHz
See footnotes at end of table.
2
AHF2812S
TABLE II. Electrical Performance Characteristics - Continued
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A Subgroups Device types Limits Unit
Min Output response to step transient load changes 6/ VOTLOAD 500 mA to/from 1000 mA 4 5,6 0 mA to/from 500 mA 4 5,6 Recovery time, step transient load changes 6/ 7/ TTLOAD 500 mA to/from 1000 mA 4,5,6 01 01 -300 -450 -500 -750
Max +300 +450 +500 +750 100 s mV pk
0 mA to 500 mA 500 mA to 0 mA Output response to transient step line changes Recovery time transient step line changes Turn on overshoot Turn on delay Load fault recovery 4/ 9/ Weight Notes: VOTLINE Input step 16 V to/from 40 V dc, IOUT = 1000 mA 4/ 8/ Input step 16 V to/from 40 V dc IOUT = 1000 mA 4/ 7/ 8/ IOUT = 0 and 1000 mA IOUT = 0 and 1000 mA 9/
4,5,6 4,5,6 4,5,6
01
1500 10 ms mV pk
01
1500
TTLINE
4,5,6
01
800
s
VTonOS TonD TrLF
4,5,6 4,5,6 4,5,6
01 01 01
600 20 20 35
mV pk ms ms grams
1/ Parameter guaranteed by line and load regulation tests. 2/ Bandwidth guaranteed by design. Tested for 20 kHz to 2 MHz. 3/ 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. 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 and 10 microseconds. 7/ Recovery time is measured from the initiation of the transient to where VOUT has returned to within 1 percent of VOUT at 50 percent load. 8/ Input step transition time between 2 and 10 microseconds. 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.
3
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Input Voltage Soldering Temperature Case Temperature -0.5V to 50V 300C for 10 seconds Operating-55C to +125C Storage -65C to +135C
AHF2815S
TABLE III. Electrical Performance Characteristics
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A subgroups Device types Limits Unit
Min Output voltage VOUT IOUT = 0 1 All 14.85
Max 15.15 V
2,3 Output current 1/ Output ripple voltage 2/ Line regulation IOUT VRIP VRLINE VIN = 18, 28, and 40 V dc, VIN = 18, 28, and 40 V dc, B.W. = 20 Hz to 2 MHz VIN = 18, 28, and 40 V dc, IOUT = 0, 1000, and 2000 mA 1,2,3 1,2,3 1 2,3 Load regulation Input current VRLOAD IIN VIN = 18, 28, and 40 V dc, IOUT = 0, 1000, and 2000 mA IOUT = 0, inhibit (pin 2) tied to input return (pin 10) IOUT = 0, inhibit (pin 2) = open Input ripple current 2/ Efficiency IRIP EFF IOUT = 2000 mA, B.W. = 20 Hz to 2 MHz IOUT = 2000 mA, 1,2,3 1 2,3 Isolation ISO Input to output or any pin to case (except pin 7) at 500 V dc, TC = +25C No effect on dc performance, TC = +25C Overload Short circuit Switching frequency FS IOUT = 2000 mA 5/ 1 All All All 1,2,3 1,2,3 All All All All All
14.70
15.30 2000 50 35 75 150 18 mV mA mA mV p-p mV
50 20 80 77 100 M mA p-p %
Capacitive load 3/ 4/ Power dissipation load fault
CL PD
4 1 1,2,3 4,5,6
All All All 01, 04 02, 05 03, 06 250 250 275
200 12 9 300 270 300
F W
kHz
See footnotes at end of table.
4
AHF2815S
TABLE III. Electrical Performance Characteristics - Continued
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A Subgroups Device types Limits Unit
Min Output response to step transient load changes 6/ VOTLOA
D
Max +800 +750 100 s mV pk
1000 mA to/from 2000 mA 0 mA to/from 1000 mA
4,5,6 4,5,6 4
All
-800 -1000
Recovery time, step transient load changes 6/ 7/
TTLOAD
1000 mA to/from 2000 mA
All
5,6 0 mA to/from 1000 mA 4 5,6 Output response to transient step line changes VOTLINE Input step 18 V to/from 40 V dc, IOUT = 2000 mA 4/ 8/ 4,5,6 04 05 06 04 05 06 All All All -1000 All
200 5 10 +1000 mV pk ms
Recovery time transient step line changes
TTLINE
Input step 18 V to/from 40 V dc IOUT = 2000 mA 4/ 7/ 8/
4,5,6
500
s
Turn on overshoot Turn on delay Load fault recovery 4/ 9/ Weight Notes:
VTonOS TonD TrLF
IOUT = 0 and 2000 mA IOUT = 0 and 2000 mA 9/
4,5,6 4,5,6 4,5,6
750 12 12 38
mV pk ms ms grams
1/ Parameter guaranteed by line and load regulation tests. 2/ Bandwidth guaranteed by design. Tested for 20 kHz to 2 MHz. 3/ 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 turnon. 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 and 10 microseconds. 7/ Recovery time is measured from the initiation of the transient to where VOUT has returned to within 1 percent of VOUT at 50 percent load. 8/ Input step transition time between 2 and 10 microseconds. 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.
5
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Input Voltage Soldering Temperature Case Temperature -0.5V to 50V 300C for 10 seconds Operating-55C to +125C Storage -65C to +135C
AHF2812D
TABLE V. Electrical Performance Characteristics.
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A subgroups Device types Limits Unit
Min Output voltage VOUT IOUT = 0 1 2,3 Output current 1/ 2/ IOUT VIN = 16, 28, and 40 V dc, each output VIN = 16, 28, and 40 V dc, B.W. = 20 Hz to 2 MHz VIN = 16, 28, and 40 V dc, IOUT = 0, 500, and 1000 mA VIN = 16, 28, and 40 V dc, IOUT = 0, 500, and 1000 mA 10 percent to 90 percent load change IOUT = 0, inhibit (pin 1) tied to input return (pin 7) IOUT = 0, inhibit (pin 1) = open Input ripple current 3/ 4/ IRIP IOUT = 1000 mA, B.W. = 20 Hz to 2 MHz IOUT = 1000 mA, TC = +25C 1,2,3 01 1,2,3 01 01 11.88 11.76 100
Max 12.12 12.24 900 mA V
Output ripple voltage 3/
VRIP
1,2,3
01
60
mV p-p
Line regulation 4/ Load regulation 4/ Cross regulation 5/ Input current
VRLINE
1,2,3
01
30
mV
VRLOAD
1,2,3
01
30
mV
VRCROS
1,2,3
01
3.0
%
IIN
1,2,3
01
12
mA
60
50
mA p-p
Efficiency
4/
EFF
1,3
01
77
%
2 Isolation ISO Input to output or any pin to case (except pin 6) at 500 V dc, TC = +25C No effect on dc performance, TC = +25C, total for both outputs Overload, TC = +25C 8/ 1 01
74 100 M
Capacitive load 6/ 7/
CL
4
01
200
F
Power dissipation load fault
PD
1,2,3
01
6
W
Short circuit, TC = +25C See footnotes at end of table.
3
6
AHF2812D
TABLE V. Electrical performance characteristics - Continued.
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A Subgroups Device types Limits Unit
Min Switching frequency 4/ FS VOTLOAD IOUT = 1000 mA 500 mA to/from 1000 mA 4,5,6 4,5,6 01 01 500 -200
Max 600 +200 kHz mV pk
Output response to step transient load changes 4/ 9/
0 mA to/from 500 mA Recovery time, step transient load changes 4/ 9/ 10/ TTLOAD 500 mA to/from 1000 mA 0 mA to/from 500 mA Output response transient step line changes 4/ 7/ 11/ Recovery time transient step line changes 4/ 7/ 10/ 11/ VOTLINE Input step from/to 16 to 40 V dc, IOUT = 1000 mA Input step from/to 16 to 40 V dc, IOUT = 1000 mA IOUT = 0 and 1000 mA IOUT = 0 and 1000 mA
4,5,6 4,5,6 4,5,6 4,5,6
01 01 01 01
-800
+800 70 1000 s
-750
+750
mV pk
TTLINE
4,5,6
01
1200
s
Turn on overshoot 4/ Turn on delay 4 12/ Load fault recovery Weight Notes: 7/
VTonOS TonD TrLF
4,5,6 4,5,6 4,5,6
01 01 01
600 25 25 38
mV pk ms ms grams
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 12 W. 3/ Bandwidth guaranteed by design. Tested for 20 kHz to 2 MHz. 4/ Load current split equally between +VOUT and -VOUT. 5/ 1.2 watt load on output under test, 1.2 watt to 10.8 watt 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 inTable 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 and 10 microseconds. 10/ Recovery time is measured from the initiation of the transient to where VOUT has returned to within 1 percent of VOUT at 50 percent load. 11/ Input step transition time between 2 and 10 microseconds. 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.
7
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Input Voltage Soldering Temperature Case Temperature -0.5V to 50V 300C for 10 seconds Operating-55C to +125C Storage -65C to +135C
AHF2815D
TABLE VI. Electrical Performance Characteristics
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A subgroups Device types Limits Unit
Min Output voltage VOUT IOUT = 0 1 2,3 Output current 1/ 2/ Output ripple 3/ voltage Line regulation 4/ Load regulation 4/ Cross regulation 5/ Input current IOUT VRIP VRLINE VIN = 16, 28, and 40 V dc, each output VIN = 16, 28, and 40 V dc, B.W. = 20 Hz to 2 MHz VIN = 16, 28, and 40 V dc, IOUT = 0, 400, and 800 mA VIN = 16, 28, and 40 V dc, IOUT = 0, 400, and 800 mA 10 percent to 90 percent load change each output IOUT = 0, inhibit (pin 1) tied to input return (pin 7) IOUT = 0, inhibit (pin 1) = open Input ripple current 3/ 4/ Efficiency 4/ IRIP EFF IOUT = 800 mA, B.W. = 20 Hz to 2 MHz IOUT = 800 mA 1,2,3 1,3 2 Isolation ISO Input to output or any pin to case (except pin 6) at 500 V dc, TC = +25C No effect on dc performance, TC = +25C, total for both outputs Overload 8/ Short circuit Switching frequency 4/ FS VOTLOAD IOUT = 800 mA 400 mA to/from 800 mA 4,5,6 4,5,6 01 01 500 -200 1 01 01 01 78 75 100 1,2,3 1,2,3 1,2,3 01 01 01 01 14.85 14.70 80
Max 15.15 15.30 720 60 35 mA mV p-p mV V
VRLOAD VRCROS
1,2,3 1,2,3
01 01
35 3.0
mV %
IIN
1,2,3
01
12
mA
55
50
mA p-p %
M
Capacitive load 6/ 7/ Power dissipation load fault
CL PD
4 1,2,3
01 01
200 6 2.5 600 +200
F W
kHz mV pk
Output response to step transient load changes 4/ 9/
0 mA to/from 400 mA See footnotes at end of table.
4,5,6
01
-800
+800
8
AHF2815D
TABLE VI. Electrical Performance Characteristics - Continued.
Test Symbol Conditions -55C TC +125C VIN = 28 V dc 5%, CL = 0 unless otherwise specified Group A Subgroups Device types Limits Unit
Min Recovery time, step transient load changes 4/ 9/ 10/ TTLOAD 400 mA to/from 800 mA 4,5,6 01
Max 70 s
0 mA to/from 400 mA Output response transient step line changes 4/ 7/ 11/ Recovery time transient step line changes 4/ 7/ 10/ 11/ Turn on overshoot 4/ Turn on delay 4/ 12/ Load fault recovery Weight Notes: 7/ VOTLINE Input step from/to 16 to 40 V dc, IOUT = 800 mA Input step from/to 16 to 40 V dc, IOUT = 800 mA IOUT = 0 and 800 mA IOUT = 0 and 800 mA
4,5,6 4,5,6
01 01 -750
500 +750 mV pk
TTLINE
4,5,6
01
1200
s
VTonOS TonD TrLF
4,5,6 4,5,6 4,5,6
01 01 01
750 25 25 38
mV pk ms ms grams
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 12 W. 3/ Bandwidth guaranteed by design. Tested for 20 kHz to 2 MHz. 4/ Load current split equally between +VOUT and -VOUT. 5/ 1.2 watt load on output under test, 1.2 watt to 10.8 watt 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 and 10 microseconds. 10/ Recovery time is measured from the initiation of the transient to where VOUT has returned to within 1 percent of VOUT at 50 percent load. 11/ Input step transition time between 2 and 10 microseconds. 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.
9
BLOCK DIAGRAM (Single Output)
8 INPUT FILTER OUTPUT FILTER 4
1
CONTROLLER
Case Ground
6
ERROR AMP & REF
7
3
APPLICATION INFORMATION
Inhibit Function Connecting the inhibit input (Pin 1) to input common (Pin 7) 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 400 A of current. The open circuit voltage of the inhibit input is 11. 1 VDC. 5
10
Thermal Management Assuming that there is no forced air flow, the package termperature rise above ambient (T) may be calculated using the following expression: T 80 A -0.7 p 0. 85 ( C) where A = the effective surface area in square inches (including heat sink if used;) P = power dissipation in watts.
STANDARDIZED MILITARY DRAWING CROSS REFERENCE
Model AHF2805S/CH AHF2812S/CH AHF2815S/CH AHF2812D/CH AHF2815D/CH Drawing Number SMD #5962-91600 SMD #5962-94568 SMD #5962-94563 SMD #5962-92111 SMD #5962-92351
PART NUMBER
AHF 28 xx x F/ x
Screening (see table) Omit for -20C to +85C ES -55C to +125C HB-- -55C to +125C CH-- Class H complaint See table for standard Mlitary drawing number
The total surface area of the AHF package is 4.9 square inches. If a worse case full load efficiency of Model 78% is assumed, then the case temperature rise can be calculated as follows:
P = POUT
Input Voltage Output Voltage 05-- 5 V DC 12--12 V DC 15--15 V DC S--Single D--Dual
[
1 1 - 1] = 12 - 1] = 3.4 W EFF .78
[
T = 80 (4.9)-0.7 (3.4)0.85 = 74C Hence, if TAMBIENT = +25C, the DC/DC converter case temperature will be approximately 100C if no heat sink or air flow is provided. To calculate the heat sink area required to maintain a specific case temperature rise, the above equation may be manipulated as follows:
A HEAT SINK = [ T ] 80P 0.85
-1.43
Package Option Omit For Standard F-Flange
-A
PKG
As an example, if a maximum case temperature rise of 50C above ambient is desired, then the required effective heat sink area is:
A
HEAT SINK
= [ 50 ] -1.43 -4.9 = 3.75 in.2 0.85 80 (3.4)
Available Screening Levels and Process Variations for AHF Series
R e quir e me nt Temperature Range Element Evaluation Internal Visual Temperature Cycle Constant Acceleration Burn- in Final Electrical (Group A) Seal, Fine & Gross External Visual *
Per Commercial Standards
M I L-STD-883 M e t hod
No No Suffix - 20 to +85C
ES ES Suffix - 55C to +125C
HB HB Suffix - 55C to +125C
CH CH Suffix - 55C to +125C MIL- PRF- 38534
2017 1010 2001 1015 MIL- PRF- 38534 1014 2009
*
Yes Cond B 500g
Yes Cond C Cond A 160hrs @ 125C - 55, +25, +125C Cond A, C Yes
Yes Cond C Cond A 160hrs @ 125C - 55, +25, +125C Cond A, C Yes
96hrs @ 125C 25C * *
11
96hrs @ 125C 25C Cond A, C Yes
MECHANICAL OUTLINE
0.03 DIA. 8 Pins (0.76) 8 1 0.205 (5.21) 0.505 (12.83) 0.705 (17.91) 0.905 (22.99)
2 7 3 4 6 5
1.105 (28.07) 1.450 (36.83)
0.09 R Typ (2.29)
0.800 (20.32) 1.120 (28.45) 0.330 (8.38) MAX
0.26 (6.60)
Tolerances: .xx =0.010, .xxx= 0.005
PIN DESIGNATION
AHF2805S AHF2812S AHF2815S Inhibit input Pin 8 Positive input N/C Outpu common t Pin 7 Input common Positive output N/C Pin 6 Cas ground e AHF2805D AHF2812D AHF2815D Inhibit input Pin 8 Positive input Positive output Outpu common t Pin 7 Input common Negative output N/C Pin 6 Case Ground
12
Pin 1 Pin 2 Pin 3 Pin 4 Pin 5
1 2 3 4 5
TOP VIEW
8
7
6
Pin 1 Pin 2 Pin 3 Pin 4 Pin 5
NOTES
13
NOTES
(c)
Lambda Advanced Analog
The information in this data sheet has been carefully checked and is believed to be accurate, however, no responsibility is assumed for possible errors. The specifications are subject to change without notice.
9847
MIL-PRF-38534 Certified
2270 Martin Avenue Santa Clara CA 95050-2781 (408) 988-4930 FAX (408) 988-2702

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