IRF M3L2812D

PD - 94519A
L-SERIES
+ 28V Input, Single/Dual Output
ADVANCED ANALOG
HIGH RELIABILITY RADIATION
TOLERANT DC/DC CONVERTERS
Description
The L-Series of DC/DC converters are radiation tolerant, high reliability devices designed for moderate radiation environments such as those encountered by low
earth orbit satellites and launch vehicles. For higher
radiation environments, the G-Series of DC/DC converters is recommended. Features include small size,
low weight and a high tolerance to total ionizing dose,
single event effects and environmental stresses such as
temperature extremes, mechanical shock, and vibration.
All components are fully derated to meet the requirements of MIL-STD-975 and MIL-STD-1547 and GSFC
PPL-21 Appendix B. Extensive documentation including Radiation Susceptibility, Thermal Analysis, Stress
Analysis and MTBF are available.
The converters incorporate a fixed frequency single forward topology with magnetic feedback and an internal
EMI filter. These converters are capable of meeting the
conducted emissions and conducted susceptibility requirements of MIL-STD-461C without any additional
components. All models include an external inhibit port
and have an adjustable output voltage. They are enclosed in a hermetic 1.5" x 2.3" x 0.425" steel package
and weigh less than 85 grams. The package utilizes
rugged ceramic feed-through copper core pins and is
sealed using parallel seam welding.
Full environmental screening includes temperature cycling, constant acceleration, fine and gross leak, and
burn-in.
Non-flight versions of the L-Series converters are available for system development purposes. Variations in
electrical specifications and screening to meet custom
requirements can be accommodated.
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Features
n Total Dose > 25K Rad(Si)
n SEE > 37 MeV.cm2/mg
n Internal EMI filter; Converter Capable of
meeting MIL-STD-461C CE03 and CS01
n Low Weight, < 85 grams
n Magnetically Coupled Feedback
n 16V to 50V DC Input Range
n Up to 25W Output Power
n Single and Dual Output Models Include
3.3, 5, 12, 15, ±5, ±12 and ±15V
n High Efficiency - to 82%
n -55°C to +125°C Operating Temperature
Range
n 100MΩ @ 500VDC Isolation
n Under-Voltage Lockout
n Short Circuit and Overload Protection
n Output Over Voltage Limiter
n Adjustable Output Voltage
n External Inhibit
n 1,500,000 Hour MTBF
Applications
n
n
Low Earth Orbit Satellites (LEO)
Launch Vehicles
1
08/20/02
L-SERIES
Circuit Description
The L-Series converters utilize a single-ended forward topology with resonant reset. The nominal
switching frequency is 500kHz. Electrical isolation
and tight output regulation are achieved through the
use of a magnetically coupled feedback. Voltage
feed-forward with duty factor limiting provides high
line rejection and protection against output over voltage in the event of an internal control loop failure.
This mechanism limits the maximum output voltage
to approximately 20% over the nominal regardless of
the line voltage.
An internal EMI filter allows the converter to meet the
conducted emissions requirements of MIL-STD-461C
on the input power leads. A single-stage output filter
reduces the typical output ripple to less than 50mV
peak-to-peak.
Output current is limited under any load fault condition to approximately 125% of rated. An overload
condition causes the converter output to behave like
a constant current source with the output voltage dropping below nominal. The converter will resume normal operation when the load current is reduced below the current limit point. This protects the converter
from both overload and short circuit conditions. The
current limit point exhibits a slightly negative temperature coefficient to reduce the possibility of thermal runaway.
2
An external inhibit port is provided to control converter operation. The converter’s operation is inhibited when this pin is pulled low. It is intended to be
driven by an open collector logic device. The pin
may be left open for normal operation and has a
nominal open circuit voltage of 10.5V with respect to
the input return (pin 2).
The output voltage of all models can be adjusted
using a single external resistor.
Design Methodology
The L-Series was developed using a proven conservative design methodology which includes selecting radiation tolerance and established reliability components and fully derating to the requirements
of MIL-STD-975 and MIL-STD-1547. Heavy derating of the power MOSFET gate and drain voltages
minimize the possibility of SEGR and SEB. A magnetic feedback circuit is utilized instead of opto-couplers to minimize temperature, radiation and aging
sensitivity. PSPICE was used extensively to predict
and optimize circuit performance for both beginning
and end-of-life. Thorough design analyses include
Radiation Susceptibility ( TREE ), Stress, Thermal,
and Reliability ( MTBF ).
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L-SERIES
Absolute Maximum Ratings
Recommended Operating Conditions
Input voltage range Output power Lead temperature Operating temperature Storage temperature -
Input voltage range Input voltage range1 Output power Operating temperature 2 Operating temperature1 -
-0.5Vdc to +60Vdc
Internally limited
+300°C for 10 seconds
-55°C to +135°C
-55°C to +135°C
1
16Vdc to +60Vdc
16Vdc to +38Vdc
0 to Max. Rated
-55°C to +125°C
-55°C to +70°C
Meets derating per MIL-STD-975
For operation at +125°C see table note 13
2
Electrical Performance Characteristics
Parameter
Group A
Subgroup
Conditions
-55°C ≤ TC ≤ +85°C
VIN = 28V DC ± 5%, CL = 0
unless otherwise specified
Input Voltage
Output Voltage ( Vout )
M3L2803R3S
M3L2805S
M3L2812S
M3L2815S
M3L2805D
M3L2812D
M3L2815D
M3L2803R3S
M3L2805S
M3L2812S
M3L2815S
M3L2805D
M3L2812D
M3L2815D
Output power ( POUT )
M3L2803R3S
All Others
Output current ( IOUT )
M3L2803R3S
M3L2805S
M3L2812S
M3L2815S
M3L2805D
M3L2812D
M3L2815D
Limits
Min
Nom
Max
Unit
18
28
50
V
3.30
5.00
12.00
15.00
±5.00
±12.00
±15.00
3.33
5.05
12.12
15.15
±5.05
±12.12
±15.15
V
V
V
V
V
V
V
1
1
1
1
1
1
1
IOUT = 100% rated load
Note 4
3.27
4.95
11.88
14.85
±4.95
±11.88
±14.85
2,3
2,3
2,3
2,3
2,3
2,3
2,3
IOUT = 100% rated load
Note 4
3.23
4.90
11.76
14.70
±4.90
±11.76
±14.70
3.37
5.10
12.24
15.30
±5.10
±12.24
±15.30
V
V
V
V
V
V
V
1,2,3
VIN = 16, 28, 50 Volts, Note 2
0
0
20
25
W
W
1,2,3
VIN = 16, 28, 50 Volts, Note 2
0
0
0
0
0
0
0
6.06
5.00
2.08
1.67
4.00
1.67
1.33
A
A
A
A
A
A
A
Either Output, Note 3
Either Output, Note 3
Either Output, Note 3
Line regulation ( VRLINE )
1,2,3
VIN = 16, 28, 50 Volts
IOUT = 0, 50%, 100% rated, Note 4
-0.5
0.5
%
Load regulation ( VRLOAD )
1,2,3
IOUT = 0, 50%, 100% rated, Note 4
VIN = 16, 28, 50 Volts
-1.0
1.0
%
1,2,3
VIN = 16, 28, 50 Volts
Duals only, Note 5
-5.0
-3.0
-3.0
5.0
3.0
3.0
%
%
%
Cross regulation ( VRCROSS )
M3L2805D
M3L2812D
M3L2815D
For Notes to Specifications, refer to page 5
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L-SERIES
Electrical Performance Characteristics
( continued )
Group A
Subgroup
Conditions
-55°C ≤ TC ≤ +85°C
VIN = 28V DC ± 5%, CL = 0
unless otherwise specified
1,2,3
Limits
Max
Unit
IOUT = 0, Pin 4 open
60
70
70
70
70
100
100
mA
mA
mA
mA
mA
mA
mA
1,2,3
Pin 4 shorted to pin 2
8
mA
1,2,3
VIN = 16, 28, 50 Volts
IOUT = 100% rated load
Notes 4, 6
35
50
70
80
80
80
80
mV p-p
mV p-p
mV p-p
mV p-p
mV p-p
mV p-p
mV p-p
1,2,3
Sync. Input (Pin 4) open
425
500
575
KHz
1,2,3
IOUT = 100% rated load
Note 4
68
75
75
75
75
75
75
75
79
80
81
79
79
80
1,2,3
Note 1
9.5
Current Limit Point
Expressed as a percentage
of full rated load current
1,2,3
Vout = 90% of Nominal, Note 4
Power dissipation, load fault (P D)
1,2,3
Short Circuit, Overload, Note 8
Output response to
step load changes (V TLD)
4,5,6
Half Load to/from Full Load, Notes 4,9
Recovery time,
step load changes (TTLD)
4,5,6
Half Load to/from Full Load, Note
4,9,10
Output response to
step line changes (VTLN)
4,5,6
16V to/from 50V
IOUT = 100% rated load, Notes 1,4,11
Recovery Time,
step line changes (TTLN)
4,5,6
16V to/from 50V
IOUT = 100% rated load, Notes
1,4,10,11
4,5,6
No Load, Full Load
Notes 4,12
Parameter
Input current, no load ( IIN )
M3L2803R3S
M3L2805S
M3L2812S
M3L2815S
M3L2805D
M3L2812D
M3L2815D
Input current inhibited
Output ripple ( V RIP )
M3L2803R3S
M3L2805S
M3L2812S
M3L2815S
M3L2805D
M3L2812D
M3L2815D
Switching frequency ( FS )
Efficiency ( EFF )
M3L2803R3S
M3L2805S
M3L2812S
M3L2815S
M3L2805D
M3L2812D
M3L2815D
Enable Input ( Inhibit Function )
open circuit voltage
drive current ( sink )
voltage range
Turn-on Response
Overshoot (VOS)
Turn-on Delay (TDLY)
Min
Nom
%
%
%
%
%
%
%
-0.5
11.5
500
50
V
µA
V
105
130
%
14
W
300
mV pk
200
µS
300
mV pk
200
µS
500
10
mV
mS
-300
-300
2
For Notes to Specifications, refer to page 5
4
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L-SERIES
Electrical Performance Characteristics
Parameter
Capacitive Load (CL)
M3L2803R3S
M3L2805S
M3L2812S
M3L2815S
M3L2805D
M3L2812D
M3L2815D
Group A
Subgroup
1
( continued )
Conditions
-55°C ≤ TC ≤ +85°C
VIN = 28V DC ± 5%, CL = 0
unless otherwise specified
Limits
IOUT = 100% rated load
No effect on DC performance
Notes 1, 4, 7
2200
1000
180
120
500
90
60
Each output on duals
Line Rejection
1
IOUT = 100% rated load
DC to 50KHz, Notes 1, 4
40
Isolation
1
Input to Output or Any Pin to Case
except pin 3, test @ 500VDC
100
50
Table I.
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
dB
85
MIL-HDBK-217F2, SF, 35°C
1.5 x 10
µF
µF
µF
µF
µF
µF
µF
MΩ
Device Weight
MTBF
Unit
6
grams
Hours
Electrical Performance Characteristics - notes
Parameter is tested as part of design characterization or after design changes. Thereafter, parameter shall be guaranteed to the
limits specified.
Parameter verified during line and load regulation tests.
Output load current must be distributed such that at least 20% of the total load current is being provided by one of the outputs.
Load current split equally between outputs on dual output models.
Cross regulation is measured with 20% rated load on output under test while changing the load on the other output from 20% to 80%
of rated.
Guaranteed for a D.C. to 20MHz bandwidth. Tested using a 20KHz to 10MHz bandwidth using the circuit shown below.
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 may interfere with the proper operation of the converter’s overload protection, causing erratic behavior during
turn-on.
Overload power dissipation is defined as the device power dissipation with the load set such that VOUT = 90% of nominal.
Load step transition time ≤ 10 µSec.
Recovery time is measured from the initiation of the transient to where VOUT has returned to within ±1% of
its steady state value.
Line step transition time ≤ 100 µSec.
Turn-on delay time from either a step application of input power or a logic low to a logic high transition on the inhibit pin (pin 4) to
the point where VOUT = 90% of nominal.
For operation at temperatures between +85°C and +125°C, derate the maximum output power linearly from 100% to 75%.
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5
L-SERIES
Radiation Performance Characteristics
Conditions
Min
Typ
Highest
Level
Tested
Total Ionizing Dose ( Gamma )
MIL-STD-883, Method 1019
Operating bias applied during exposure,
Full Rated Load, VIN = 28V
25
40
60
KRads
(Si)
Single Event Effects
SEU, SEL, SEGR, SEB
Heavy ions (LET)
Operating bias applied during exposure,
Full Rated Load, VIN = 28V
37
82
82
MeV•cm
/mg
Dose Rate ( Gamma Dot )
Temporary Saturation
Survival
MIL-STD-883, Method 1023
Operating bias applied during exposure,
Full Rated Load, VIN = 28V
1E8
1E10
1.5E9
Rads
(Si)/sec
Neutron Fluence
MIL-STD-883, Method 1017
3E12
8E12
Neutrons
2
/cm
Proton Fluence
E > 10MeV
TBD
N/A
protons
2
/cm
Test
Unit
2
Device Screening
Test Inspection
Method
Condition
Element Evaluation
MIL-PRF-38534 class H equivalent with SEM
Nondestructive Bond Pull
MIL-STD-883, Method 2023
Internal Visual
MIL-STD-883, Method 2017
Temperature Cycling
MIL-STD-883, Method 1010
C
Constant Acceleration
MIL-STD-883, Method 2001 (2k-g)
A, Y1 axis only
Electrical
In accordance with
device specification
Burn-in
MIL-STD-883, Method 1015
Final Electrical ( Group A )
160 Hours
In accordance with
device specification
Seal
Fine Leak
Gross Leak
External Visual
6
MIL-STD-883, Method 1014
A1
C
MIL-STD-883, Method 2009
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L-SERIES
Vin
1
EMI
FILTER
+10.5V
INHIBIT
4
RETURN
2
CASE
GROUND
3
7
+OUTPUT
6
OUTPUT
RETURN
5
OUTPUT
ADJUST
BIAS
SUPPLY
+
EA
-
PWM
CONTROLLER
RAMP
GEN.
SAMPLE
&
HOLD
FEEDBACK
TRIGGER
Block Diagram - Single Output
Vin
1
EMI
FILTER
8
+OUTPUT
7
RETURN
6
-OUTPUT
5
OUTPUT
ADJUST
+10.5V
INHIBIT
4
RETURN
2
CASE
GROUND
3
BIAS
SUPPLY
+
EA
-
PWM
CONTROLLER
RAMP
GEN.
SAMPLE
&
HOLD
FEEDBACK
TRIGGER
Block Diagram - Dual Output
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7
L-SERIES
100
90
80
70
dB-uA
60
CEO3 LIMIT
50
40
30
20
10
0
1E3
1E4
1E5
1E6
1E7
1E8
1E7
1E8
Frequency ( Hz )
Conducted Emissions, Common Mode
100
90
80
70
dB-uA
60
CEO3 LIMIT
50
40
30
20
10
0
1E3
1E4
1E5
1E6
Frequency ( Hz )
Conducted Emissions, Normal Mode
8
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L-SERIES
0
-10
-20
-30
dB
-40
-50
-60
-70
-80
-90
-100
1E2
1E3
1E4
1E5
Frequency ( Hz )
M3L2805S Line Rejection (CS01)
0
-10
-20
-30
dB
-40
-50
-60
-70
-80
-90
-100
1E2
1E3
1E4
1E5
Frequency ( Hz )
M3L2815D Line Rejection (CS01)
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9
L-SERIES
0
-10
-20
-30
dB
-40
-50
-60
-70
-80
-90
-100
1E2
1E3
1E4
1E5
Frequency ( Hz )
M3L2815D Line Rejections (CS01)
50 Ω
50 Ω C oax
1 µF
O s c illis c o p e o r E q u iv a le n t
w ith 1 0 M H z B a n d w id th .
M u ltip ly re a d in g s b y 2 .
0 .1 µ F
+ Vout
50 Ω
T e rm in a tio n
DUT
R e tu rn
R L fo r I R A T E D
Circuit for Measuring Output Ripple Voltage
10
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L-SERIES
Mechanical Diagram
2.300
0.375
ø 0.128
4 Plcs
1.550
0.050
0.25 T yp.
0.270
8
0.470
1
0.400
7
0.400
1.000
R ef
1.500 1.750 2.000
3
6
4
5
2
2 Eq S paces
@ 0.200
0.400
0.200
Pin ø
0.040
0.350
0.220
0.850
2.80
R ef
0.250
0.425
M ax
Pin Designation (Single/Dual)
Pin Number
Single
Dual
Pin 1
+ Input
+ Input
Pin 2
Input Return
Input Return
Pin 3
Case
Case
Pin 4
Inhibit
Inhibit
Pin 5
Output Adjust
Output Adjust
Pin 6
Output Return
- Vout
Pin 7
+ Vout
Output Common
Pin 8
NC
+ Vout
T o le ra n ce : .X X = ±0 .0 1
.X X X = ±0 .0 0 5
Part Number
M3L 28 05 S
Model
Input Voltage
28 = 28V Nominal
Outputs
S = Single
D = Dual
Output Voltage
03R3 = 3.3V, 05 = 5V
12 = 12V, 15 = 15V
WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, Tel: (310) 322 3331
ADVANCED ANALOG: 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. 02/03
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