LT3083
Adjustable 3A
Single Resistor Low
Dropout Regulator
FEATURES
DESCRIPTION
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Outputs May be Paralleled for Higher Current and
The LT®3083 is a 3A low dropout linear regulator that can
be paralleled to increase output current or spread heat on
surfacemountedboards.Architectedasaprecisioncurrent
source and voltage follower, this new regulator finds use
in many applications requiring high current, adjustability
to zero, and no heat sink. The device also brings out the
collectorofthepasstransistortoallowlowdropoutopera-
tion—downto310mV—whenusedwithmultiplesupplies.
Heat Spreading
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Output Current: 3A
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Single Resistor Programs Output Voltage
50μA Set Pin Current: 1% Initial Accuracy
Output Adjustable to 0V
Low Output Noise: 40μV
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(10Hz to 100kHz)
RMS
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Wide Input Voltage Range: 1.2V to 23V
(DD-Pak and TO-220 Packages)
Low Dropout Voltage: 310mV
A key feature of the LT3083 is the capability to supply a
wide output voltage range. By using a reference current
throughasingleresistor,theoutputvoltageisprogrammed
to any level between zero and 23V (DD-PAK and TO-220
packages). The LT3083 is stable with 10μF of capacitance
on the output, and the IC is stable with small ceramic ca-
pacitors that do not require additional ESR as is common
with other regulators.
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<1mV Load Regulation
<0.001%/V Line Regulation
Minimum Load Current: 1mA
Stable with Minimum 10μF Ceramic Capacitor
Current Limit with Foldback and Overtemperature
Protection
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Available in 16-Lead TSSOP, 12-Lead 4mm × 4mm
DFN, 5-Lead TO-220 and 5-Lead Surface Mount
DD-PAK Packages
Internal protection circuitry includes current limiting and
thermal limiting. The LT3083 is offered in the 16-lead
TSSOP (with an exposed pad for better thermal character-
istics), 12-lead 4mm × 4mm DFN (also with an exposed
pad), 5-lead TO-220, and 5-lead surface mount DD-PAK
packages.
APPLICATIONS
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High Current All Surface Mount Supply
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High Efficiency Linear Regulator
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Post Regulator for Switching Supplies
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
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Low Parts Count Variable Voltage Supply
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Low Output Voltage Power Supplies
TYPICAL APPLICATION
Set Pin Current Distribution
1.5V to 0.9V at 3A Supply (Using 3.3V VCONTROL
)
N = 1052
V
CONTROL
3.3V
4.7μF
10μF
V
CONTROL
V
= 0.9V
= 3A
LT3083
V
OUT
MAX
IN
IN
OUT
I
1.5V
*
10μF
SET
R
MIN
909Ω
3083 TA01a
*OPTIONAL FOR
MINIMUM 1mA LOAD
REQUIREMENT
R
18.2k
1%
SET
0.1μF
49
49.5
50
50.5
51
SET PIN CURRENT DISTRIBUTION (μA)
3083 TA01b
3083f
1