Linear Dimensions LND1083 7.5 a, 5 a, 3 a low dropout positive adjustable regulator Datasheet

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DATA SHEET
LND1083/84/85
7.5 A, 5 A, 3 A Low Dropout Positive Adjustable Regulators
GENERAL DESCRIPTION
FEATURES
The LND1083/LND1084/LND1085 series of
positive adjustable regulators are designed to
provide 7.5A, 5A and 3A with higher efficiency
than currently available devices. All internal
circuitry is designed to operate down to 1V
input to output differential and the dropout
voltage is fully specified as a function of load
current. Dropout is guaranteed at a maximum
of 1.5V at maximum output current. On-chip
trimming adjusts the reference voltage to
1%.Current limit is also trimmed, minimizing
the stress on both the regulator and power
source circuitry under overload conditions.
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Three terminal Adjustable
Output Current of 3A, 5A or 7.5A
Operates Down to 1V dropout
Guaranteed Dropout Voltage at
Multiple Current Levels
0.015% Line regulation
0.01% Load Regulation
100% Thermal Limit Burn-In
The LND1083/LND1084/LND1085 devices are
pin compatible with older 3 terminal regulators.
A 10µF output capacitor is required on these
new devices: however, this is usually included
in most regulator designs.
TYPICAL APPLICATION DATA
5V, 5A Regulator
APPLICATIONS
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High Efficiency Linear Regulators
Post Regulators for Switching
Supplies
Constant Current Regulators
Battery Chargers
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
LND1083/84/85
Package Information
T Package TO–220 Plastic
Front View
K PackageTO-3 Metal Can
Bottom View
P Package TO–3P Plastic
Front View
ABSOULUTE MAXIMUM RATING
SYMBOL
PARAMETER
PD
Power Dissipation
Input to Output Voltage Differential «M»
grades
«C»grades
VIN
TJ
TSTG
TLEAD
Operating Junction Temperature Range
«M»grades
Control section
Power Transistor
«C»Grades
Control Section
Power Transistor
Storage Temperature
Lead Temperature(soldering,10 sec)
MAXIMUM
UNITS
Internally Limited
W
35
30
V
-55 to 150
-55 to 200
ºC
0 to 125
0 to 150
-65 to 150
300
ºC
ºC
DEVICE SELECTION GUIDE
DEVICE
OUTPUT CURRENT
LND1083
LND1084
LND1085
7.5A
5.0A
3.0A
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
LND1083/84/85
ELECTRICAL CHARACTERISTICS
(See Note 1)
Parameter
Reference Voltage
Line Regulation
Load Regulation
Dropout Voltage
Current Limit
LND1083
LND1084
LND1085
Minimum Load Current
Thermal regulation
LND1083
LND1083
LND1085
Ripple Rejection
Adjust Pin Current
Adjust Pin Current
Change
Temperature Stability
Long Term Stability
RMS output Noise(%
of Vout)
Test conditions
IOut=10mA, Tj=25ºC
(Vin-Vout)=3V(K Package Only)
10mA<=Iout <=I full load
1.5V <=(Vin-Vout) <= 25V(Note 3)
Iload=10mA, 1.5<=(Vin-Vout) <=15V,
TJ =25ºC
M grade
15V<=(Vin-Vout) <=35V
C grade
15V <=(Vin-Vout) <=30V(Notes1,2)
(Vin-Vout)=3V
10mA <=Iout <=Ifullload.
Tj=25ºC(notes 1,2,3,5)
∆Vref=1%,Iout =Ifullload (See Notes 4,5)
(Vin-Vout)=5V
(Vin-Vout)=25V
(Vin-Vout)=5V
(Vin-Vout)=25V
(Vin-Vout)=5V
(Vin-Vout)=25V
(Vin-Vout)=25V
Min
Typ
Max
1.238
1.250
1.262
V
*
1.225
*
*
*
*
*
*
*
*
*
*
*
TA=125º C,1000Hrs
TA=25º C
10Hz ≤f ≤10kHz
*
1.250
0.015
0.035
1.270
0.2
0.2
0.05
0.5
0.05
0.5
0.1
0.2
1.3
0.3
0.4
1.5
%
*
8.0
0.4
5.5
0.3
3.2
0.2
TA =25ºC, 30ms pulse
f=120Hz,
Cadj=25µF Cout=25µF tantalum,
Iout=I fullload , (Vin-Vout)=3V(Note5)
Tj=25ºC
10mA ≤Iout ≤ Ifullload ,
1.5 V ≤ (Vin-Vout)=25V(Note 5)
Units
60
9.5
1.0
6.5
0.6
4.0
0.5
5
10
0.002
0.003
0.004
0.01
0.015
0.02
%
V
A
75
mA
%/W
dB
*
55
120
*
0.2
5
*
0.5
0.3
1
µA
%
0.003
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
LND1083/84/85
The * denotes the specifications which apply over the full operating temperature range.
Note 1: See thermal regulation specifications for changes in output voltage due to heating effects. Load
and line regulations are measured at a constant junction temperature by low duty cycle pulse testing.
Note 2: Line and load regulation are guaranteed up to the maximum power dissipation (60W for the
LND1083, 45W for the LND1084 (K, P) 30W for the LND1084 (T) and 30W for the LND1085). Power
dissipation will not be available over the full input/output voltage range.
Note 3:Ifillload is defined in the current limit curves. Ifillload curve is defined as the minimum value of current
limit as a function of input to output voltage.
Note 4: Dropout voltage is specified over the full output current range of the device.
Note 5: For LND1083 IfillLoad is 5Afor -55ºC ≤Tj ≤ -40ºand 7.5A for Tj >-40ºC
BLOCK DIAGRAM
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
LND1083/84/85
APPLICATIONS INFORMATION
The LND1083 family of three-terminal
adjustable regulators is easy to use and has all
the protection features that are expected in
high performance voltage regulators.
Stability
The circuit design used in the LND1083 series
requires the use of an output capacitor as part
of the device frequency compensation. The
addition of 150 µF aluminum electrolytic or a
22 µF solid tantalum on the output will ensure
stability for all operating conditions.
Microsecond surge currents of 50A to 100A
can be handled by the internal diode
between the Output pin and the Input pin of
the device. In normal operations it is difficult
to get those values of surge currents even
with the use of large output capacitance.
Only with high value output capacitors, such
as 1000 to 5000µF and with the Input pin
instantaneously shorted to ground, can
damage occur. A diode from output to input
is recommended (Figure 2).
Output Voltage
The LND1083 develops a 1.25V reference
voltage between the Output pin and the Adjust
pin (Figure 1). Placing a resistor between
these two terminals causes a constant current
to flow through R1 and down though R2 to set
the output voltage. In general R1 is chosen so
that this current is the specified minimum load
current of 10mA. The current out of the Adjust
pin is small as compared to the current from
R1and can be ignored.
Figure 1 Output Voltage
Protection Diodes
In normal operation LND1083 family does not
need any protection diodes between the
adjustment pin and the output and from the
out to the input to prevent die overstresses.
Internal resistors are limiting the internal
current paths on the ADJ pin. Therefore
even with bypass capacitors on the adjust pin
no protection diode is needed to ensure
device safety under short-circuit conditions.
Figure 2. Protection Diodes.
Thermal Considerations
The LND1083 series have internal power and
thermal-limiting circuitry designed to protect
the device under overload conditions.
However, maximum junction temperature
ratings should not be exceeded under
continuous normal load conditions. Careful
consideration must be given to all sources of
thermal resistance from junction to ambient,
including junction-to-case, case to-heat sink
interface and heat sink resistance itself.
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
LND1083/84/85
TYPICAL APPLICATIONS
Improving ripple rejection
1.2V to 15V adjustable regulator
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
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