PD-97812
LSO SERIES
HYBRID-HIGH RELIABILITY
RADIATION HARDENED
DC-DC CONVERTER
28V Input, Single/Dual Output
Description
The LSO Series of DC-DC converters are, high reliability
devices designed for hostile radiation hardened
environments. The design is based on the heritage-rich
LS Series with enhanced functional performance and
an inclusion of an output overvoltage protection. The
LSO Series provide up to 30 watts output power, small
size, low weight, integrated EMI filtering and a high
tolerance to environmental stresses such as radiation,
temperature extremes, mechanical shock, and vibration.
All components are fully de-rated to meet the requirements
of MIL-STD-1547, MIL-STD-975 and NASA EEE-INST002. Extensive documentation including, thermal
analysis, stress analysis and reliability predictions are
available.
The LSO Series of 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
requirements of MIL-STD-461C without any additional
components. All models include an external inhibit port
and have an adjustable output voltage. The converters
are overload, short circuit and output over-voltage
protected. They are enclosed in a hermetic 3.5" x 2.5" x
0.475" H steel package and weigh less than 125 grams.
The package utilizes rugged ceramic feed-through
copper core pins and is sealed using parallel seam
welding.
Manufactured in a facility fully qualified to MIL-PRF38534, these converters are fabricated utilizing DLA
qualified processes. For available screening options,
refer to device screening table in the data sheet.
Variations in electrical specifications and screening to
meet custom requirements can be accommodated.
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LSO
Features
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18 to 40V DC Input Range
Total Ionization Dose > 100K Rad(Si)
SEE Hardened to LET (Heavy Ions) up to
2
82 MeV•cm /mg (SEU, SEL, SEGB, SEGR)
Internal EMI filter; Converter Capable of
meeting MIL-STD-461C CE03
Derated per MIL-STD-1547, MIL-STD-975
and NASA EEE-INST-002
Magnetically Coupled Feedback
Up to 30W Output Power
Single and Dual Output Models Include
1.5, 1.8, 2.5, 3.3, 5, 12, 15, ±5, ±12 and ±15V
Remote Sense Compensation for Single
Output
Latch-off Output Overvoltage Protection
Input Current Telemetry
Input Undervoltage Lockout with Latching
Mode Options
High Efficiency - to 81%
20MΩ @ 100VDC Isolation
Undervoltage Protection
Short Circuit and Overload Protection
Adjustable Output Voltage
Adjustable External OVP-115% to 125%
External Inhibit
Low Weight, < 125 grams
4000000 Hour MTBF (SF)
Applications
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Geo Synchronous Satellite
Low Earth Orbit
Deep Space Probe
Communication and Display Systems
Payload and Experiment LVPS
1
08/27/13
LSO SERIES
28V Input, Single/Dual Output
Circuit Description
The LSO 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.
An internal EMI filter allows the converter to meet
the conducted emissions requirements of MIL-STD461C on the input power leads.
Functional Notes
Input Current Telemetry: The LSO Series single
and dual output models also feature an input current
telemetry with a magnitude of 0 to 3.3V full scale.
The voltage signal at this pin (Pin 7) with respect to
Output Return (Pin 12) is equal to 1.5 times the input
current (Vin TLM (V) =1.5 *Input Current (A)+/-0.1V)
Short Circuit and Overload Protection: Output
current is limited under any load fault condition to
approximately 125% of rated. An overload condition
causes the converter output voltage to drop 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.
Input Undervoltage Lockout (UVLO) and
Undervoltage Release (UVR): The converter is
designed to be protected against an undervoltage
condition. The converter will be in a non-functional
(UVLO) mode when the input voltage is pproximately
15.5V or less. The converter will turn on when the
input voltage rises to 15.5V to 17.9V (defined as
UVR threshold) and will provide a regulated output
as the input voltage reaches 18V.
To take advantage of the latch-up feature, the U/V
Latch Pin (Pin 5) should be shorted (with less than
100 ohms) to the Inhibit Return Pin (Pin 4). Note that
in this mode the converter will latch off if an
undervoltage condition lasts more than 1milli-sec.
The converter is reset by a shorted Enable Input pin
command followed by an open Enable Input pin
command.
Output Overvoltage Protection: The converter
also features an output over-voltage protection.
One OVP circuitry for each output for the dual output
models. In an event the voltage output exceeds a
preset voltage threshold of approximately 120 +/5% of nominal voltage output, the converter will
turn off. The input power to the converter or the
signal at the Inhibit pin must be recycled (connecting
and removing the Inhibit pin to/from Inhibit Return
pin) to turn on the converter. This event is possible
only if the converter shuts off due to a false triggering.
The OVP threshold voltage can also be reset to
within 115% to 125% of nominal output voltage
with two external resistors. Refer to the Application
Notes section of the data sheet on page 9.
Inhibit (On/Off Command) : 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 4V with respect to the inhibit return (Pin 4).
Output Voltage Adjustment: The output voltage
of all models can be adjusted greater or less than
the nominal output voltage using a single external
resistor. Refer to the Application Notes section of
the data sheet on page 9.
Should the input voltage drops below 16.5V to 14.5V
(defined as UVLO threshold), the converter will turn
off and remains off so long as the input voltage
remains under the UVLO threshold. The converter
will resume a normal operation when the input line
rises above the UVR threshold. However, the
converter can be configured to remain in a latch-up
mode if desired.
2
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LSO SERIES
28V Input, Single/Dual Output
Design Methodology
The LSO Series was developed using a proven
conservative design methodology derived from other
space level designs that includes selection of
established reliability components and fully derating
to the requirements of MIL-STD-1547, MIL-PRF-975
and NASA EEE-INST-002 except for the CDR type
ceramic capacitors, a capacitor with 50V rating is
used for in-circuit voltage stress of less than 10V. A
magnetic feedback circuit is utilized instead of opto
-couplers to minimize temperature, aging and
radiation sensitivity. PSPICE was used extensively
to predict and optimize circuit performance for both
beginning and end-of-life. Thorough design
analyses include stress, thermal, and reliability
(MTBF).
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3
LSO SERIES
28V Input, Single/Dual Output
Absolute Maximum Ratings
Recommended Operating Conditions
Input voltage range
Output power
Lead temperature
Operating case temperature
Storage temperature
Input voltage range
Output power
Operating case temperature
Operating case temperature
-0.5Vdc to +60Vdc
Internally limited
+300°C for 10 seconds
-55°C to +125°C (Note 13)
-55°C to +135°C
1
+18Vdc to +40Vdc
0 to Max. Rated
-55°C to +85°C
-55°C to +70°C
1. Meets MIL-STD-1547, MIL-STD-975 and NASA EEE-INST-002
up to the input voltage at 38.6V.
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 )
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
LSO2805S
LSO2812S
LSO2815S
LSO2805D
LSO2812D
LSO2815D
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
LSO2805S
LSO2812S
LSO2815S
LSO2805D
LSO2812D
LSO2815D
Output power ( POUT )
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
All Others
Output current ( IOUT )
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
LSO2805S
LSO2812S
LSO2815S
LSO2805D
LSO2812D
LSO2815D
1
1
1
1
1
1
1
1
1
1
IOUT = 100% rated load
Note 4
2,3
2,3
2,3
2,3
2,3
2,3
2,3
2,3
2,3
2,3
IOUT = 100% rated load
Notes 4, 13
VIN = 18, 28, 40 Volts, Note 2
1,2,3
1,2,3
VIN = 18, 28, 40 Volts, Note 2
Either Output, Note 3
Either Output, Note 3
Either Output, Note 3
Limits
Min
Nom
Max
Unit
18
28
40
V
1.47
1.77
2.47
3.27
4.95
11.88
14.85
±4.95
±11.88
±14.85
1.50
1.80
2.50
3.30
5.00
12.00
15.00
±5.00
±12.00
±15.00
1.53
1.83
2.53
3.33
5.05
12.12
15.15
±5.05
±12.12
±15.15
1.43
1.73
2.43
3.23
4.90
11.76
14.70
±4.90
±11.76
±14.70
1.57
1.87
2.57
3.37
5.10
12.24
15.30
±5.10
±12.24
±15.30
0
0
0
0
0
12
14.4
20
25
30
0
0
0
0
0
0
0
0
0
0
8.0
8.0
8.0
7.57
6.0
2.5
2.0
4.8
2.3
1.6
V
V
W
A
For Notes to Electrical Performance Characteristics, refer to page 7
4
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LSO SERIES
28V Input, Single/Dual Output
Electrical Performance Characteristics
Parameter
Group A
Subgroup
Line regulation ( VRLINE )
All Single and Dual Output Models
Load regulation ( VRLOAD )
All Single Output Models
Total regulation ( Line and Load )
Cross regulation (VRCROSS )
LSO2805D
LSO2812D
LSO2815D
Input Current, no load (IIN )
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
LSO2805S
LSO2812S
LSO2815S
LSO2805D
LSO2812D
LSO2815D
Input current inhibited
Output Ripple (VRIP)
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
LSO2805S
LSO2812S
LSO2815S
LSO2805D
LSO2812D
LSO2815D
Switching frequency (FS )
Efficiency (EFF )
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
LSO2805S
LSO2812S
LSO2815S
LSO2805D
LSO2812D
LSO2815D
Input undervoltage lockout (UVLO)
(turn off when input voltage
decreassing)
Input undervoltage release (UVR)
(turn on when input voltage rising)
Input undervoltage
Hysteresis (UVR-UVLO)
Input current telemetry ratio( ICT)
(continued)
Conditions
-55°C ≤ TC ≤ +85°C
VIN = 28V DC ± 5%, CL = 0
unless otherwise specified
Limits
Min
Nom
Max
Unit
VIN = 18, 28, 40 Volts
IOUT = 0, 50%, 100% rated, Note 4
-0.5
0.5
%
1,2,3
VIN = 18, 28, 40 Volts
IOUT = 0, 50%, 100% rated, Note 4
-1.0
1.0
%
1,2,3
VIN = 18 to 40 Volts
Min load to full load
Dual model is measured
from +Output to –Output, Note 13
-1.0
1.0
%
VIN = 18, 28, 40 Volts
Duals only, Note 5
-5.0
-3.0
-3.0
5.0
3.0
3.0
%
1,2,3
1,2,3
1,2,3
60
60
60
60
70
70
70
70
100
100
IOUT = 0, Pin 3 open
1,2,3
Pin 4 shorted to Pin 3
8.0
1,2,3
VIN = 18, 28, 40 Volts
IOUT = 100% rated load
Notes 4, 6
35
35
35
35
50
70
50
50
50
50
1,2,3
1,2,3
IOUT = 100% rated load
Note 4
425
500
60
63
67
71
77
77
77
76
78
78
62
65
69
73
80
80
80
79
81
81
575
mA
mA
mV p-p
KHz
%
1,2,3
No load to full load, Notes 1, 4
14.5
16.5
V
1,2,3
No load to full load, Notes 1, 4
15.5
17.9
V
1,2,3
No load to full load, Notes 1, 4
1.0
3.0
V
1,2,3
IOUT = 100% rated load, Note 4
1.4
1.6
V/A
For Notes to Electrical Performance Characteristics, refer to page 7
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5
LSO SERIES
28V Input, Single/Dual Output
Electrical Performance Characteristics
Parameter
Overvoltage protection (OVP)
Output voltage threshold
(for single and each of dual
output models)
Enable Input ( Inhibit Function )
open circuit voltage
drive current ( sink )
voltage range
Current Limit Point
Expressed as a percentage
of full rated load current
(continued)
Group A
Subgroup
Conditions
-55°C ≤ TC ≤ +85°C
VIN = 28V DC ± 5%, CL = 0
unless otherwise specified
1,2,3
No load to full load, Notes 1, 4
115
125
% of
nominal
Vout
Note 1
3.0
-0.5
5.0
5.0
50
V
mA
V
105
145
%
16
W
300
mV pk
200
µs
300
mV pk
200
µs
50
mV
10
ms
1,2,3
VOUT = 90% of Nominal, Note 4
1,2,3
Short Circuit, Overload, Note 8
Output response to
step load changes (VTLD )
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, Notes
4,9,10
Power dissipation, load fault (PD )
Output response to
step line changes (VTLN )
18V to/from 40V
IOUT = 100% rated load, Notes 1,4,11
Recovery Time,
step line changes (TTLN )
18V to/from 40V
IOUT = 100% rated load, Notes
1, 4,10,11
Turn-on Overshoot (VOS )
All Single and Dual Output Models
Turn-on Delay ( TDLY )
All Single and Dual Output Models
4,5,6
Capacitive Load (CL )
LSO2801R5S
LSO2801R8S
LSO2802R5S
LSO2803R3S
LSO2805S
LSO2812S
LSO2815S
LSO2805D
LSO2812D
LSO2815D
10% Load, Full Load
Notes 4,12
Limits
Min
Nom
-300
-300
0
2500
2500
2500
2200
1000
180
120
500
90
60
IOUT = 100% rated load
No effect on DC performance
Notes 1, 4, 7
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 6, test @ 100VDC
20
50
4.0 x 10
µF
dB
125
MIL-HDBK-217F2, SF, 35°C
Note 14
Unit
MΩ
Device Weight
MTBF
Max
6
g
Hr
For Notes to Electrical Performance Characteristics, refer to page 7
6
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LSO SERIES
28V Input, Single/Dual Output
Notes for Electrical Performance Characteristics Table
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
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 in Fig.1.
Capacitive load may be any value from 0 to the maximum limit without compromising dc performance. For
a capacitive load in excess of the maximum limit, consult the factory.
Overload power dissipation is defined as the device power dissipation with the load set such that VOUT =
90% of nominal.
Load step transition time ≤ 10µs.
Recovery time is measured from the initiation of the transient to where V OUT has returned to within ±1% of
its steady state value.
Line step transition time ≤ 100µs.
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 3) to the point where V OUT = 90% of nominal.
End of ife (EOL) is ±3%
MIL-HDBK MOSFET failure rates replaced by empirical failure rate data supplied by Intenational Rectifier.
Fig. 1 - Circuit for measuring Output Ripple Voltage
50 Ω
50Ω Coax
1 µF
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Radiation Performance Characteristics
Test Inspection
Method
Total Ionizing Dose (Gamma)
Operating bias applied during exposure,
Min
Typ
Unit
100
150
Krads(Si)
MIL-PRF-883, Method 1019
Full Rated Load, VIN = 28V
Heavy Ions (LET)
Single Event Effects
Operating bias applied during exposure,
SEU, SEL, SEGR, SEB
Full Rated Load, VIN = 28V
82
2
MeVxcm /mg
Test lab: Cyclotron Institute
Texas A & M University
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7
LSO SERIES
28V Input, Single/Dual Output
Fig. 2 - Single Output Block Diagram
LSO28XXS
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LSO SERIES
28V Input, Single/Dual Output
Application Notes:
Fig. 4 - Typical Connections Diagram
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Inhibit Function:
Remote Sense:
The converter is disabled when the INHIBIT pin is
shorted to the INHIBIT RETURN with an impedance less
than or equal to 1K ohm, and that the converter be
enabled when the impedance between the INHIBIT pin
and INHIBIT RETURN is greater than or equal to 500K
ohms.
A remote sense feature maintains the desired output
voltage regulation at the load. It corrects the voltage drop
along the conductors between converter’s output and the
load. To use this function connect ±sense pins directly to
the load as shown in Fig. 6. To use a converter without
remote sense function, connect the ±sense pins to output
pins respectively. This function is available just on single
output models.
Fig. 5 - Inhibit Function
Fig. 6 - Remote Sense - Single Models
9
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9
LSO SERIES
28V Input, Single/Dual Output
Output Voltage Adjustment:
Output of LSO singles and duals can be adjusted to be
greater or less the nominal output voltage with an external
resistor. However, the ranges of the output voltages are
limited depending on the model as specified in Table 1 and
Table 2. An approximate value of the resistor can be
determined using the following formula.
For Single Output Model:
Radj =
Constants
A
B
C
D
Output voltage
Low range
4.750 to 5.000
588.3 x106
264.5 x106
7950
39716
A - (B * V out )
(C * V out ) - D
A - (B * 2 * Vout )
(C * 2 * V out ) - D
Where:
Radj is the external resistor in ohms, as shown in Fig 7.
Power rating of the resistor shall be ≥ 0.125 W. Metal film
resistor with temperature coefficient of ≤ ± 50 ppm and
tolerance of ≤ 1% is recommended. However, the final
selection is dependent on specific design requirements.
Vovp is the output voltage in volts.
A, B, C and D are unique constants depending on every
model as shown in Table 1 for single output models and
Table 2 for dual output models.
Placement of Radj: An external resistor must be added
in order to trim the output voltage of a LSO converter.
The placement of a Radj resistor must be connected as
shown in Fig. 7.
Singles: Radj is placed across Out Adj and ± Sense
pins. For output voltage greater than nominal voltage,
Radj is placed from Out Adj to –Sense. To have output
voltage less than nominal voltage, place Radj across Out
Adj and +Sense.
Constants
A
B
C
D
Output voltage
Low range
14.250 to 15.000
588.3 x106
264.5 x106
7950
39716
Constants
A
B
C
D
Output voltage
Low range
r4.750 to r5.000
1012.4x106
395.0x106
6840
68344
Constants
A
B
C
D
10
Output voltage
High range
r5.000 to r5.250
1011.5x10 6
60.1x106
6840
68344
Table 5. LSO2815D. Output Voltage Ranges and Constants
Constants
A
B
C
D
Output voltage
Low range
r14.250 to r15.000
2780.2x106
974.8x106
6260
187646
Output voltage
High range
r15.000 to r15.750
2777.9x10 6
55.0x106
6260
187646
Fig. 7 - Output Voltage Adjustment
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Table 1. LSO2803R3S. Output Voltage Ranges and Constants
Output voltage
High range
3.300 to 3.465
466.0x106
84.0 x106
9550
31489
Output voltage
High range
15.000 to 15.750
1451.2x10 6
57.5 x106
6540
39717
Table 4. LSO2805D. Output Voltage Ranges and Constants
Duals: Radj is placed across Out Adj and ± Output pins
respectively.
Output voltage
Low range
3.135 to 3.300
466.4 x106
238.3 x106
9550
31489
Output voltage
High range
5.000 to 5.250
587.8x106
699.6 x106
7950
39717
Table 3. LSO2815S. Output Voltage Ranges and Constants
For Dual Output Model:
Radj =
Table 2. LSO2805S. Output Voltage Ranges and Constants
/62;;'
2XWSXW
5HWXUQ
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2XWSXW
$'-83
2XW$GM
5DGM
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LSO SERIES
28V Input, Single/Dual Output
Table 7. LSO Duals. OVP Exeternal
OVP External Adjustment:
Over-voltage Protection threshold of LSO singles and
duals can be adjusted to be greater or less the nominal
OVP with a couple of external resistors. Lower resistors,
R1 and R2 are 10KΩ resistors, while Radj set the new
OVP threshold as stated in Table 6 for single output
models and Table 7 for dual output models. Ranges of
LSO series converter can be adjusted from 115% to
125% of the nominal output voltage. See Fig.8 to place
external resistors.
An approximate value of the resistor can be determined
using the following formula.
Radj =
LSO2805DS
Range
OVP
Vo* (115%)
Vo* (116%)
Vo* (117%)
Vo* (118%)
Vo* (119%)
Vo* (120%)
Vo* (121%)
Vo* (122%)
Vo* (123%)
Vo* (124%)
Vo* (125%)
5.75
5.80
5.85
5.90
5.95
6.00
6.05
6.10
6.15
6.20
6.25
Where:
Radj is the upper external resistor in kilo-ohms, as shown
in Fig 8. Power rating of the resistor shall be
≥ 0.125 W. Metal film resistor with temperature
coefficient of ≤ ± 50 ppm and tolerance of ≤ 1% is
recommended. However, the final selection is dependent
on specific design requirements.
/62;;6
/62;;'
Duals: Radj(+OVP) is placed across +Output and +OVP
Adj pins and R1 from +OVP Adj to -Return. Radj(-OVP) is
placed across +Return and -OVP Adj pins while R2 is
placed across -OVP Adj to –Output.
Vo*
Vo*
Vo*
Vo*
Vo*
Vo*
Vo*
Vo*
Vo*
Vo*
Vo*
(115%)
(116%)
(117%)
(118%)
(119%)
(120%)
(121%)
(122%)
(123%)
(124%)
(125%)
3.79
3.82
3.86
3.89
3.92
3.96
3.99
4.02
4.05
4.09
4.12
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OVP
5.75
5.80
5.85
5.90
5.95
6.00
6.05
6.10
6.15
6.20
6.25
293
2XWSXW
293$GM
5HWXUQ
293$GM
2XWSXW
5DGM
293
5
N
5DGM
293
5
N
'8$/
Stacking Outputs:
On dual output models, output can be stacked to double
the output voltage as shown in Fig 9.
Table 6. LSO Singles. OVP Exeternal
OVP
293$GM
2XWSXW
Singles: Radj(OVP) is placed across +Output and OVP
Adj pins and R1 from OVP Adj to -Output.
Range
6,1*/(
Placement of Radj: Two external resistors must be
added in order to set new OVP threshold.
Radj
(KΩ)
26
28
31
33
36
39
42
46
51
56
63
2XWSXW
5
N
A, B, C and D are unique constants depending on every
model.
LSO2805S
17.25
17.40
17.55
17.70
17.85
18.00
18.15
18.30
18.45
18.60
18.75
Radj
(KΩ)
101
107
113
121
128
137
146
157
169
183
199
5DGM
Vovp is the output voltage protection limit in volts.
Radj
(KΩ)
13
15
16
18
20
22
25
28
31
36
41
OVP
Fig. 8 - OVP with External Adjustment
(A * Vovp ) - B
C - (D * Vovp )
LSO2803R3S
LSO2815D
Radj
(KΩ)
26
28
30
33
36
39
43
47
51
57
64
LSO2815S
OVP
17.25
17.40
17.55
17.70
17.85
18.00
18.15
18.30
18.45
18.60
18.75
Radj
(KΩ)
102
108
114
121
128
137
146
157
168
181
197
Fig. 9 - Stacked Outputs on Dual Models
2XWSXW /62;;'
5HWXUQ 2XWSXW /2$'
11
LSO SERIES
28V Input, Single/Dual Output
Typical Performance Curves: 25°C TC, 28 VDC VIN, Rated Load, unless otherwise specified
Fig. 10 - LSO2805S Efficiency
Fig. 11 - LSO2805S Output Ripple
Fig. 12 - LSO2805S Step Line Response,
18V to/from 40V.
Fig. 13 - LSO2805S Step Load Response,
Half Load to/from Full Load, 0.25A/µs Slew Rate.
Fig. 14 - LSO2805S Turn On Response
Fig. 15 - LSO2805S Loop Response,
Phase = 60.01q and Gain = -17.81dB
12
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LSO SERIES
28V Input, Single/Dual Output
Typical Performance Curves: 25°C TC, 28 VDC VIN, Rated Load, unless otherwise specified
Fig. 16 - LSO2815D Efficiency
Fig. 17 - LSO2815D Output Ripple
Fig. 18 - LSO2815D Step Line Response,
18V to/from 40V.
Fig. 19 - LSO2815D Step Load Response,
Half Load to/from Full Load, 0.05A/µs Slew Rate.
Fig. 20 - LSO2815D Turn On Response
Fig. 21 - LSO2815D Loop response,
Phase = 61.46q and Gain = -22.45dB
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LSO SERIES
28V Input, Single/Dual Output
Typical Performance Curves: 25°C TC, 28 VDC VIN, Rated Load, unless otherwise specified
Fig. 22 - LSO2803R3S Efficiency.
Fig. 23 - LSO2815S Efficiency.
Fig. 24 - LSO2805D Efficiency.
14
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LSO SERIES
28V Input, Single/Dual Output
Typical Performance Curves: 25°C TC, 28 VDC VIN, Rated Load, unless otherwise specified
Fig. 25 - LSO2805S Full Load, Common Mode, Neagtive Lead.
Fig. 26 - LSO2805S Full Load, Common Mode, Positive Lead.
Fig. 27 - LSO2805S Full Load, Common Mode, Positive Lead.
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LSO SERIES
28V Input, Single/Dual Output
Typical Performance Curves: 25°C TC, 28 VDC VIN, Rated Load, unless otherwise specified
Fig. 28 - LSO2815D Full Load, Common Mode, Neagtive Lead.
Fig. 29 - LSO2815D Full Load, Common Mode, Positive Lead.
Fig. 30 - LSO2815D Full Load, Common Mode, Positive Lead.
16
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LSO SERIES
28V Input, Single/Dual Output
Mechanical Outline
3.055 MAX.
0.500
0.080
Max.
2.00
R0.0625
4 places
0.30
0.50
0.20
13
1
12
2
11
10
0.60
9
3
8
4
7
5
6
2.055
MAX.
2.30
0.200 Typ.
Noncum.
1.400
Ref.
2.500
Pin
Ø0.040
0.45
1.10
0.260
FLANGE DETAIL
3.50
Ref.
2
.06
R0
0.25
0.25
0.475
MAX.
5
0.14
0.40
Tolerance :
.XX
.XXX
±0.01
±0.005
Note: Standard leads finish is solder dipped.
Pin Designation (Single/Dual)
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Pin #
Single
Dual
1
Input
Input
2
Input Return
Input Return
3
Inhibit
Inhibit
4
Inhibit Return
Inhibit Return
5
U/V Latch
U/V Latch
6
Case Ground
Case Ground
7
Input Current Telemetry
Input Current Telemetry
8
Output Adjust
Output Adjust
9
- Sense
- OVP Adjust
10
+ Sense
+ OVP Adjust
11
OVP Adjust
- Output
12
13
- Output
+ Output
Output Return
+ Output
17
LSO SERIES
28V Input, Single/Dual Output
Device Screening
Requirement
MIL-STD-883 Method
No Suffix (Flight Model) EM (Engineering Model)
Temperature Range
-55°C to +85°C
-55°C to +85°C
Element Evaluation
MIL-PRF-38534
Class K
N/ A
Non-Destruction Bond Pull
2023
YES
N/ A
Internal Visual
2017
YES
c
Temperature Cycle
1010
Cond C
Cond C
Constant Acceleration
2001, Y1 Axis
3000 Gs
3000 Gs
PIND
2020
Cond A
N/ A
48 hrs @ 125°C
320 hrs @ 125°C
Burn-In
1015
Final Electrical (Group A)
MIL-PRF-38534 & Specification
-55°C, +25°C,+ 85°C
-55°C, +25°C, +85°C
PDA
MIL-PRF-38534
2%
Seal, Fine and Gross
1014
Cond A, C
N/ A
Cond A
Radiographic
2012
Yes
N/ A
External Visual
2009
Yes
(2 x 160 hrs)
c
Notes:
c Best commercial practice
Part Numbering
LSO 28 05 S /EM
Model
Input Voltage
Nominal
28 = 28V
Output Voltage
01R5 = 1.5V, 01R8 = 1.8V,
02R5 = 2.5V, 03R3 = 3.3V,
05 = 5V, 12 = 12V, 15 = 15V
Screening Level
(Please refer to Screening Table)
No Suffix, EM
Output
S = Single
D = Dual
WORLD HEADQUARTERS: 101 N, Sepulveda Blvd., El Segundo, California 90245, USA Tel: (310) 252-7105
IR SAN JOSE: 2520 Junction Avenue, San Jose, California 95134, USA Tel: (408) 434-5000
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Data and specifications subject to change without notice. 08/2013
18
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