LT3082 - 200mA Single Resistor Low Dropout Linear Regulator

LT3082
200mA Single Resistor Low
Dropout Linear Regulator
FEATURES
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DESCRIPTION
Outputs May Be Paralleled for Higher Output
Current or Heat Spreading
Maximum Output Current: 200mA
Wide Input Voltage Range: 1.2V to 40V
Output Adjustable to 0V
Stable with Minimum 2.2μF Ceramic Capacitors
Single Resistor Sets Output Voltage
Initial Set Pin Current Accuracy: 1%
Low Output Noise: 33μVRMS (10Hz to 100kHz)
Reverse-Battery Protection
Reverse-Current Protection
<1mV Load Regulation Typical
<0.001%/V Line Regulation Typical
Current Limit and Thermal Shutdown Protection
Available in 8-Lead SOT-23, 3-Lead SOT-223 and
8-Lead 3mm × 3mm DFN Packages
APPLICATIONS
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The LT®3082 is a 200mA low dropout linear regulator that
can be paralleled to increase output current or spread heat
in surface mounted boards. Architected as a precision
current source and voltage follower, this regulator benefits
many applications requiring high current, adjustability to
zero and no heat sink. The LT3082 withstands reverse
input voltages and reverse output-to-input voltages without
reverse-current flow.
A key feature of the LT3082 is the capability to supply a
wide output voltage range. A precision “0” TC 10μA reference current source drives a single resistor to program
the output voltage to any level between zero and 38.5V.
The LT3082 is stable with only 2.2μF of capacitance on
the output; the IC uses small ceramic capacitors that
do not require additional ESR as is common with other
regulators.
Internal protection circuitry includes reverse-battery and
reverse-current protection, current limiting and thermal limiting. The LT3082 is offered in the thermally enhanced 8-lead TSOT-23, 3-lead SOT-223 and 8-lead 3mm
× 3mm DFN packages.
All-Surface Mount Power Supply
Post Regulator for Switching Supplies
Low Parts Count Variable Voltage Supply
Low Output Voltage Supply
Battery Powered Regulator
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.
TYPICAL APPLICATION
SET Pin Current vs Temperature
Variable Output Voltage Battery Powered Supply
SET PIN CURRENT (μA)
1μF
10.075
LT3082
IN
9V
10μA
+
–
SET
OUT
VOUT = 10μA • RSET
CSET
0.1μF
RSET
500k
10.100
COUT
2.2μF
10.050
10.025
10.000
9.975
9.950
9.925
9.900
–50 –25
3082 TA01a
0
25 50 75 100 125 150
TEMPERATURE (°C)
3082 TA01b
3082f
1
LT3082
ABSOLUTE MAXIMUM RATINGS
(Note 1) All Voltages Relative to VOUT
IN Pin Voltage Relative to SET, OUT ........................±40V
SET Pin Current (Note 6) .....................................±15mA
SET Pin Voltage (Relative to OUT, Note 6) ...............±10V
Output Short-Circuit Duration .......................... Indefinite
Operating Junction Temperature Range (Notes 2, 8)
E, I Grades ......................................... –40°C to 125°C
MP Grade........................................... –55°C to 125°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (ST, TS8 Packages Only)
Soldering, 10 sec .............................................. 300°C
PIN CONFIGURATION
TOP VIEW
OUT
1
OUT
2
NC
3
SET
4
TOP VIEW
3
8 IN
9
7 IN
TAB IS OUT
IN
2
OUT
1
SET
TOP VIEW
NC 1
OUT 2
OUT 3
OUT 4
6 NC
5 NC
ST PACKAGE
3-LEAD PLASTIC SOT-223
DD PACKAGE
8-LEAD (3mm s 3mm) PLASTIC DFN
TJMAX = 125°C, θJA = 24°C/W, θJC = 15°C/W
TAB IS OUT, MUST BE SOLDERED TO OUT ON THE PCB;
SEE THE APPLICATIONS INFORMATION SECTION
TJMAX = 125°C, θJA = 28°C/W, θJC = 3°C/W
EXPOSED PAD (PIN 9) IS OUT, MUST BE SOLDERED TO OUT ON
THE PCB; SEE THE APPLICATIONS INFORMATION SECTION
8 IN
7 IN
6 NC
5 SET
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
TJMAX = 125°C, θJA = 57°C/W, θJC = 15°C/W
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT3082EDD#PBF
LT3082EDD#TRPBF
LDYT
8-Lead (3mm × 3mm) Plastic DFN
–40°C to 125°C
LT3082IDD#PBF
LT3082IDD#TRPBF
LDYT
8-Lead (3mm × 3mm) Plastic DFN
–40°C to 125°C
LT3082EST#PBF
LT3082EST#TRPBF
3082
3-Lead Plastic SOT-223
–40°C to 125°C
LT3082IST#PBF
LT3082IST#TRPBF
3082
3-Lead Plastic SOT-223
–40°C to 125°C
LT3082MPST#PBF
LT3082MPST#TRPBF
3082MP
3-Lead Plastic SOT-223
–55°C to 125°C
LT3082ETS8#PBF
LT3082ETS8#TRPBF
LTDYV
8-Lead Plastic SOT-23
–40°C to 125°C
LT3082ITS8#PBF
LT3082ITS8#TRPBF
LTDYV
8-Lead Plastic SOT-23
–40°C to 125°C
LEAD BASED FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT3082EDD
LT3082EDD#TR
LDYT
8-Lead (3mm × 3mm) Plastic DFN
–40°C to 125°C
LT3082IDD
LT3082IDD#TR
LDYT
8-Lead (3mm × 3mm) Plastic DFN
–40°C to 125°C
LT3082EST
LT3082EST#TR
3082
3-Lead Plastic SOT-223
–40°C to 125°C
LT3082IST
LT3082IST#TR
3082
3-Lead Plastic SOT-223
–40°C to 125°C
LT3082MPST
LT3082MPST#TR
3082MP
3-Lead Plastic SOT-223
–55°C to 125°C
LT3082ETS8
LT3082ETS8#TR
LTDYV
8-Lead Plastic SOT-23
–40°C to 125°C
LT3082ITS8
LT3082ITS8#TR
LTDYV
8-Lead Plastic SOT-23
–40°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
3082f
2
LT3082
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TJ = 25°C. (Note 2)
PARAMETER
SET Pin Current
CONDITIONS
MIN
TYP
MAX
UNITS
10
10
10.10
10.20
μA
μA
2
4
mV
mV
–0.1
–0.5
–2
nA
mV
0.03
0.003
0.2
0.010
ISET
VIN = 2V, ILOAD = 1mA
2V ≤ VIN ≤ 40V, 1mA ≤ ILOAD ≤ 200mA
l
9.90
9.80
Offset Voltage (VOUT – VSET)
VOS
VIN = 2V, ILOAD = 1mA
VIN = 2V, ILOAD = 1mA
l
–2
–4
Load Regulation (Note 7)
ΔISET
ΔVOS
ΔILOAD = 1mA to 200mA
ΔILOAD = 1mA to 200mA
l
ΔISET
ΔVOS
ΔVIN = 2V to 40V, ILOAD = 1mA
ΔVIN = 2V to 40V, ILOAD = 1mA
Line Regulation
nA/V
mV/V
Minimum Load Current (Note 3)
2V ≤ VIN ≤ 40V
l
300
500
μA
Dropout Voltage (Note 4)
ILOAD = 10mA
ILOAD = 200mA
l
l
1.22
1.3
1.45
1.65
V
V
Current Limit
VIN = 5V, VSET = 0V, VOUT = –0.1V
l
Error Amplifier RMS Output Noise (Note 5)
300
mA
ILOAD = 200mA, 10Hz ≤ f ≤ 100kHz, COUT = 10μF,
CSET = 0.1μF
33
μVRMS
Reference Current RMS Output Noise (Note 5)
10Hz ≤ f ≤ 100kHz
0.7
nARMS
Ripple Rejection
f = 120Hz, VRIPPLE = 0.5VP-P, ILOAD = 0.1A,
COUT = 2.2μF, CSET = 0.1μF
f = 10kHz
f = 1MHz
90
dB
75
20
dB
dB
Thermal Regulation
ISET
10ms Pulse
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: Unless otherwise specified, all voltages are with respect to VOUT.
The LT3082E is tested and specified under pulse load conditions such
that TJ ≅ TA. The LT3082E is 100% tested at TA = 25°C. Performance at
–40°C and 125°C is assured by design, characterization, and correlation
with statistical process controls. The LT3082I is guaranteed to meet all
data sheet specifications over the full –40°C to 125°C operating junction
temperature range. The LT3082MP is 100% tested and guaranteed over
the –55°C to 125°C operating junction temperature range.
Note 3: Minimum load current is equivalent to the quiescent current of
the part. Since all quiescent and drive current is delivered to the output
of the part, the minimum load current is the minimum current required to
maintain regulation.
200
0.003
%/W
Note 4: For the LT3082, dropout is specified as the minimum input-tooutput voltage differential required supplying a given output current.
Note 5: Adding a small capacitor across the reference current resistor
lowers output noise. Adding this capacitor bypasses the resistor shot
noise and reference current noise; output noise is then equal to error
amplifier noise (see the Applications Information section).
Note 6: Diodes with series 1k resistors clamp the SET pin to the OUT pin.
These diodes and resistors only carry current under transient overloads.
Note 7: Load regulation is Kelvin-sensed at the package.
Note 8: This IC includes overtemperature protection that protects the
device during momentary overload conditions. Junction temperature
exceeds the maximum operating junction temperature when
overtemperature protection is active. Continuous operation above the
specified maximum operating junction temperature may impair device
reliability.
3082f
3
LT3082
TYPICAL PERFORMANCE CHARACTERISTICS
SET Pin Current
2.0
N = 1326
10.075
1.5
10.050
1.0
OFFSET VOLTAGE (mV)
SET PIN CURRENT (μA)
Offset Voltage (VOUT – VSET)
SET Pin Current Distribution
10.100
10.025
10.000
9.975
9.950
9.925
0.5
0
–0.5
–1.0
–1.5
9.900
–50 –25
0
9.80
25 50 75 100 125 150
TEMPERATURE (°C)
3082 G01
–2.0
–50 –25
10
10.20
9.90
10.10
SET PIN CURRENT DISTRIBUTION (μA)
0
25 50 75 100 125 150
TEMPERATURE (°C)
3082 G03
3082 G02
Offset Voltage
Offset Voltage Distribution
1.00
N = 1326
Offset Voltage
100
ILOAD = 1mA
50
–2
0
–1
1
VOS DISTRIBUTION (mV)
2
0
0.50
OFFSET VOLTAGE (μV)
OFFSET VOLTAGE (mV)
0.75
0.25
0
–0.25
–0.50
–50
–100
–150
–200
–250
–300
–0.75
–350
–1.00
–400
0
5
10 15 20 25 30 35
INPUT-TO-OUTPUT VOLTAGE (V)
0
40
3082 G05
50
150
100
LOAD CURRENT (mA)
200
3082 G06
3082 G04
ΔILOAD = 1mA TO 200mA
VIN – VOUT = 3V
10
0
–50
0
CHANGE IN REFERENCE CURRENT
–10
–100
–20
–150
–30
–200
–40
–250
(VOUT – VSET)
–50
CHANGE IN OFFSET VOLTAGE
–300
–60
–350
–70
–400
–50 –25
0
–80
25 50 75 100 125 150
TEMPERATURE (°C)
Minimum Load Current
600
MINIMUM LOAD CURRENT (μA)
CHANGE IN OFFSET VOLTAGE WITH LOAD (μV)
50
20
CHANGE IN REFERENCE CURRENT WITH LOAD (nA)
Load Regulation
100
500
400
300
200
100
0
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
3082 G08
3082 G07
3082f
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LT3082
TYPICAL PERFORMANCE CHARACTERISTICS
Dropout Voltage
Dropout Voltage
TJ = –55°C
1.2
TJ = 25°C
1.0
TJ = 125°C
0.8
0.6
0.4
0.2
0
50 75 100 125 150 175 200
LOAD CURRENT (mA)
1.2
ILOAD = 200mA
1.0
ILOAD = 100mA
0.8
0.6
0.4
0.2
350
300
250
200
150
100
50
0
–50 –25
TJ = 25°C
0
25 50 75 100 125 150
0
TEMPERATURE (°C)
3082 G10
0
2
6
8
10
4
INPUT-TO-OUTPUT DIFFERENTIAL VOLTAGE (V)
3082 G11
3082 G09
Current Limit
Load Transient Response
450
400
350
300
250
200
150
100
200
150
100
50
0
–50
–100
50
0
–50 –25
0
250
–150
VIN = 7V
VOUT = 0V
0
0
50 100 150 200 250 300 350 400 450 500
LOAD
CURRENT (mA)
OUTPUT VOLTAGE DEVIATION (mV)
500
TIME (μs)
VOUT = 1V
CSET = 0.1μF
CIN = 1μF CERAMIC
ΔILOAD = 10mA to 200mA
COUT = 2.2μF CERAMIC
25 50 75 100 125 150
TEMPERATURE (°C)
3082 G12
3082 G13
Line Transient Response
Turn-On Response
OUTPUT VOLTAGE (V)
25
CURRENT LIMIT (mA)
0
400
CURRENT LIMIT (mA)
DROPOUT VOLTAGE (VIN – VOUT) (V)
1.4
OUTPUT VOLTAGE
DEVIATION (mV)
DROPOUT VOLTAGE (VIN – VOUT) (V)
Current Limit
1.4
1.6
60
40
20
0
–20
4
2
0
0
50 100 150 200 250 300 350 400 450 500
TIME (μs)
VOUT = 1V
CSET = 0.1μF
CIN = 1μF CERAMIC
ILOAD = 10mA
COUT = 2.2μF CERAMIC
1.0
0.5
0
4
2
0
0
INPUT
VOLTAGE (V)
6
1.5
INPUT
VOLTAGE (V)
–40
2.0
10 20 30 40 50 60 70 80 90 100
TIME (μs)
COUT = 2.2μF CERAMIC CSET = 0
RSET = 100k
RLOAD = 5Ω
3082 G14
3082f
5
LT3082
TYPICAL PERFORMANCE CHARACTERISTICS
Residual Output for Less Than
Minimum Load Current
Ripple Rejection
800
SET PIN = 0V
89
VOUT
600
100
VIN = 36V
RTEST
500
VIN = 5V
400
300
200
80
60
CSET =
0.1μF
40
20
100
0
0
0
1000
RTEST (Ω)
2000
88
RIPPLE REJECTION (dB)
VIN
RIPPLE REJECTION (dB)
700
OUTPUT VOLTAGE (mV)
Ripple Rejection (120Hz)
90
120
VIN = VOUT(NOMINAL) + 3V
RIPPLE = 500mVP-P
ILOAD = 200mA
COUT = 2.2μF
10
100
3082 G16
CSET = 0
1k
10k 100k
FREQUENCY (Hz)
87
86
85
84
83
82
81
1M
10M
VIN = VOUT(NOMINAL) + 2V
RIPPLE = 500mVP-P, f = 120Hz
ILOAD = 0.2A
CSET = 0, COUT = 2.2μF
80
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
3082 G18
3082 G17
NOISE SPECTRAL DENSITY (nV/√Hz)
1k
1k
100
100
10
10
1.0
1
10
100
1k
10k
FREQUENCY (Hz)
0.1
100k
REFERENCE CURRENT NOISE SPECTRAL DENSITY (pA /√Hz)
Noise Spectral Density
10k
Output Voltage Noise
VBAT = 3.6V
ICPO = 200μA
CCPO = 2.2ΩF
VOUT
100μV/DIV
TIME 1ms/DIV
3082 G20
VOUT = 1V
COUT = 2.2μF
RSET = 100k ILOAD = 200mA
CSET = 0.1μF
3082 G19
3082f
6
LT3082
PIN FUNCTIONS
(DD/ST/TS8)
IN (Pins 7, 8/Pin 3/Pins 7, 8): Input. This pin supplies
power to regulate internal circuitry and supply output load
current. For the device to operate properly and regulate,
the voltage on this pin must be 1.2V to 1.4V above the
OUT pin (depending on output load current—see the
dropout voltage specifications in the Electrical Characteristics table).
NC (Pins 3, 5, 6/NA/Pins 1, 6): No Connection. These
pins have no connection to internal circuitry and may be
tied to IN, OUT, GND or floated.
OUT (Pins 1, 2/Pin 2/Pins 2, 3, 4): Output. This is the
power output of the device. The LT3082 requires a 0.5mA
minimum load current or the output will not regulate.
SET (Pin 4/Pin 1/Pin 5): Set. This pin is the error amplifier’s noninverting input and also sets the operating bias
point of the circuit. A fixed 10μA current source flows
out of this pin. A single external resistor programs VOUT.
Output voltage range is 0V to 38.5V.
Exposed Pad/Tab (Pin 9/Tab/NA): Output. The Exposed
Pad of the DFN package and the Tab of the SOT-223
package are tied internally to OUT. Tie them directly to OUT
pins (Pins 1, 2/Pin 2) at the PCB. The amount of copper area
and planes connected to the Exposed Pad/Tab determine
the effective thermal resistance of the packages (see the
Applications Information section).
BLOCK DIAGRAM
IN
10μA
+
–
SET
OUT
3082 BD
3082f
7
LT3082
APPLICATIONS INFORMATION
Introduction
The LT3082 regulator is easy to use and has all the protection features expected in high performance regulators.
Included are reverse-input, reverse-output and reverse
input-to-output protection for sensitive circuitry and loads.
Additional protection includes short-circuit protection and
thermal shutdown with hysteresis.
The LT3082 fits well in applications needing multiple rails.
This new architecture adjusts down to zero with a single
resistor, handling modern low voltage digital IC’s as well
as allowing easy parallel operation and thermal management without heat sinks. Adjusting to zero output allows
shutting off the powered circuitry. When the input is preregulated—such as a 5V or 3.3V input supply—external
resistors can help spread the heat.
A precision “0” TC 10μA reference current source connects
to the noninverting input of a power operational amplifier.
The power operational amplifier provides a low impedance
buffered output to the voltage on the noninverting input.
A single resistor from the noninverting input to ground
sets the output voltage. If this resistor is set to 0Ω, zero
output voltage results. Therefore, any output voltage between zero and the maximum defined by the input power
supply voltage is obtainable.
The benefit of using a true internal current source as the
reference, as opposed to a bootstrapped reference in older
regulators, is not so obvious in this architecture. A true
Programming Output Voltage
The LT3082 generates a 10μA reference current that
flows out of the SET pin. Connecting a resistor from SET
to GND generates a voltage that becomes the reference
point for the error amplifier (see Figure 1). The reference
voltage equals 10μA multiplied by the value of the SET
pin resistor. Any voltage may be generated and there
is no minimum output voltage for the regulator. Table
1 lists many common output voltages and the closest
standard 1% resistor values used to generate that output
voltage.
Regulation of the output voltage requires a minimum load
current of 0.5mA. For a true 0V output operation, return
this minimum 0.5mA load current to a negative supply
voltage.
LT3082
IN
CIN
reference current source allows the regulator to have gain
and frequency response independent of the impedance on
the positive input. On older adjustable regulators, such as
the LT1086, loop gain changes with output voltage and
bandwidth changes if the adjustment pin is bypassed
to ground. For the LT3082, loop gain is unchanged with
output voltage changes or bypassing. Output regulation
is not a fixed percentage of output voltage, but is a fixed
fraction of millivolts. Use of a true current source allows
all of the gain in the buffer amplifier to provide regulation,
and none of that gain is needed to amplify up the reference
to a higher output voltage.
10μA
+
–
SET
OUT
VOUT = 10μA • RSET
CSET
RSET
COUT
RLOAD
3082 F01
Figure 1. Basic Adjustable Regulator
3082f
8
LT3082
APPLICATIONS INFORMATION
Table 1. 1% Resistors for Common Output Voltages
VOUT (V)
RSET (k)
1
100
1.2
121
1.5
150
1.8
182
2.5
249
3.3
332
5
499
With a 10μA current source generating the reference
voltage, leakage paths to or from the SET pin can create
errors in the reference and output voltages. High quality insulation should be used (e.g., Teflon, Kel-F). The
cleaning of all insulating surfaces to remove fluxes and
other residues may be required. Surface coating may be
necessary to provide a moisture barrier in high humidity
environments.
Minimize board leakage by encircling the SET pin and
circuitry with a guard ring that is operated at a potential
close to itself. Tie the guard ring to the OUT pin. Guarding
both sides of the circuit board is required. Bulk leakage
reduction depends on the guard ring width. 10nA of leakage into or out of the SET pin and its associated circuitry
creates a 0.1% reference voltage error. Leakages of this
magnitude, coupled with other sources of leakage, can
cause significant offset voltage and reference drift, especially over the possible operating temperature range.
Figure 2 depicts an example guard ring layout.
If guard ring techniques are used, this bootstraps any
stray capacitance at the SET pin. Since the SET pin is
a high impedance node, unwanted signals may couple
into the SET pin and cause erratic behavior. This will
be most noticeable when operating with minimum
output capacitors at full load current. The easiest way
to remedy this is to bypass the SET pin with a small
amount of capacitance from SET to ground; 10pF to
20pF is sufficient.
Stability and Output Capacitance
The LT3082 requires an output capacitor for stability. It
is designed to be stable with most low ESR capacitors
(typically ceramic, tantalum or low ESR electrolytic). A
minimum output capacitor of 2.2μF with an ESR of 0.5Ω
or less is recommended to prevent oscillations. Larger
values of output capacitance decrease peak deviations
and provide improved transient response for larger load
current changes. Bypass capacitors, used to decouple
individual components powered by the LT3082, increase
the effective output capacitor value. For improvement in
transient response performance, place a capacitor across
the voltage setting resistor. Capacitors up to 1μF can be
used. This bypass capacitor reduces system noise as well,
but start-up time is proportional to the time constant of
the voltage setting resistor (RSET in Figure 1) and SET pin
bypass capacitor.
Give extra consideration to the use of ceramic capacitors.
Ceramic capacitors are manufactured with a variety of di-
OUT
SET
GND
3082 F02
Figure 2. Example Guard Ring Layout for DFN Package
3082f
9
LT3082
APPLICATIONS INFORMATION
electrics, each with different behavior across temperature
and applied voltage. The most common dielectrics used
are specified with EIA temperature characteristic codes of
Z5U, Y5V, X5R and X7R. The Z5U and Y5V dielectrics are
good for providing high capacitances in a small package,
but they tend to have strong voltage and temperature
coefficients, as shown in Figures 3 and 4. When used with
a 5V regulator, a 16V 10μF Y5V capacitor can exhibit an
effective value as low as 1μF to 2μF for the DC bias voltage
applied and over the operating temperature range. The X5R
and X7R dielectrics result in more stable characteristics
and are more suitable for use as the output capacitor.
The X7R type has better stability across temperature,
while the X5R is less expensive and is available in higher
values. Care still must be exercised when using X5R and
X7R capacitors. The X5R and X7R codes only specify
operating temperature range and maximum capacitance
change over temperature. Capacitance change due to DC
bias with X5R and X7R capacitors is better than with Y5V
and Z5U capacitors, but can still be significant enough to
drop capacitor values below appropriate levels. Capacitor
DC bias characteristics tend to improve as component
case size increases, but expected capacitance at operating
voltage should be verified.
Stability and Input Capacitance
Voltage and temperature coefficients are not the only
sources of problems. Some ceramic capacitors have a
piezoelectric response. A piezoelectric device generates
voltage across its terminals due to mechanical stress. In a
ceramic capacitor, the stress can be induced by vibrations
in the system or thermal transients.
One of two ways reduces a wire’s self-inductance. One
method divides the current flowing towards the LT3082
between two parallel conductors. In this case, the farther
apart the wires are from each other, the more the self-inductance is reduced; up to a 50% reduction when placed
a few inches apart. Splitting the wires basically connects
Low ESR, ceramic input bypass capacitors are acceptable
for applications without long input leads. However, applications connecting a power supply to an LT3082 circuit’s IN
and GND pins with long input wires combined with a low
ESR, ceramic input capacitors are prone to voltage spikes,
reliability concerns and application-specific board oscillations. The input wire inductance found in many battery
powered applications, combined with the low ESR ceramic
input capacitor, forms a high-Q LC resonant tank circuit. In
some instances this resonant frequency beats against the
output current dependent LDO bandwidth and interferes
with proper operation. Simple circuit modifications/solutions are then required. This behavior is not indicative of
LT3082 instability, but is a common ceramic input bypass
capacitor application issue.
The self-inductance, or isolated inductance, of a wire is
directly proportional to its length. Wire diameter is not a
major factor on its self-inductance. For example, the selfinductance of a 2-AWG isolated wire (diameter = 0.26") is
about half the self-inductance of a 30-AWG wire (diameter
= 0.01"). One foot of 30-AWG wire has about 465nH of
self-inductance.
40
20
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10μF
20
X5R
CHANGE IN VALUE (%)
CHANGE IN VALUE (%)
0
–20
–40
–60
Y5V
–80
–100
–20
–40
2
4
8
6
10 12
DC BIAS VOLTAGE (V)
14
16
3082 F03
Figure 3. Ceramic Capacitor DC Bias Characteristics
Y5V
–60
–80
0
X5R
0
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10μF
–100
–50 –25
50
25
75
0
TEMPERATURE (°C)
100
125
3082 F04
Figure 4. Ceramic Capacitor Temperature Characteristics
3082f
10
LT3082
APPLICATIONS INFORMATION
two equal inductors in parallel, but placing them in close
proximity gives the wires mutual inductance adding to
the self-inductance. The second and most effective way
to reduce overall inductance is to place both forward and
return current conductors (the input and GND wires) in
very close proximity. Two 30-AWG wires separated by
only 0.02", used as forward- and return-current conductors, reduce the overall self-inductance to approximately
one-fifth that of a single isolated wire.
Spreading the devices on the PC board also spreads the
heat. Series input resistors can further spread the heat if
the input-to-output difference is high.
LT3082
IN
10μA
+
–
SET
If wiring modifications are not permissible for the applications, including series resistance between the power supply
and the input of the LT3082 also stabilizes the application.
As little as 0.1Ω to 0.5Ω, often less, is effective in damping
the LC resonance. If the added impedance between the
power supply and the input is unacceptable, adding ESR to
the input capacitor also provides the necessary damping of
the LC resonance. However, the required ESR is generally
higher than the series impedance required.
VIN
4.8V TO
40V
OUT
50mΩ
LT3082
IN
10μA
+
–
1μF
SET
OUT
50mΩ
165k
VOUT, 3.3V
0.4A
10μF
3082 F05
Paralleling Devices
Figure 5. Parallel Devices
Higher output current is obtained by paralleling multiple
LT3082s together. Tie the individual SET pins together and
tie the individual IN pins together. Connect the outputs in
common using small pieces of PC trace as ballast resistors
to promote equal current sharing. PC trace resistance in
mΩ/inch is shown in Table 2. Ballasting requires only a
tiny area on the PCB.
Table 2. PC Board Trace Resistance
WEIGHT (oz)
10mil WIDTH
1
54.3
2
27.1
Trace resistance is measured in mΩ/in
20mil WIDTH
27.1
13.6
The worst-case room temperature offset, only ±2mV
between the SET pin and the OUT pin, allows the use of
very small ballast resistors.
As shown in Figure 5, each LT3082 has a small 50mΩ
ballast resistor, which at full output current gives better
than 80% equalized sharing of the current. The external
resistance of 50mΩ (25mΩ for the two devices in parallel) adds only about 10mV of output regulation drop at an
output of 0.4A. Even with an output voltage as low as 1V,
this adds only 1% to the regulation. Of course, paralleling
more than two LT3082s yields even higher output current.
Quieting the Noise
The LT3082 offers numerous noise performance advantages. Every linear regulator has its sources of noise. In
general, a linear regulator’s critical noise source is the
reference. In addition, consider the error amplifier’s noise
contribution along with the resistor divider’s noise gain.
Many traditional low noise regulators bond out the voltage
reference to an external pin (usually through a large value
resistor) to allow for bypassing and noise reduction. The
LT3082 does not use a traditional voltage reference like
other linear regulators. Instead, it uses a 10μA reference
current. The 10μA current source generates noise current
levels of 2.7pA/√Hz (0.7nARMS over the 10Hz to 100kHz
bandwidth). The equivalent voltage noise equals the RMS
noise current multiplied by the resistor value.
The SET pin resistor generates spot noise equal to √4kTR
(k = Boltzmann’s constant, 1.38 • 10–23J/°K, and T is absolute temperature) which is RMS summed with the voltage
noise If the application requires lower noise performance,
bypass the voltage/current setting resistor with a capacitor
to GND. Note that this noise-reduction capacitor increases
start-up time as a factor of the RC time constant.
3082f
11
LT3082
APPLICATIONS INFORMATION
The LT3082 uses a unity-gain follower from the SET pin
to the OUT pin. Therefore, multiple possibilities exist
(besides a SET pin resistor) to set output voltage. For
example, using a high accuracy voltage reference from
SET to GND removes the errors in output voltage due to
reference current tolerance and resistor tolerance. Active
driving of the SET pin is acceptable.
The typical noise scenario for a linear regulator is that the
output voltage setting resistor divider gains up the noise
reference, especially if VOUT is much greater than VREF. The
LT3082’s noise advantage is that the unity-gain follower
presents no noise gain whatsoever from the SET pin to the
output. Thus, noise figures do not increase accordingly.
Error amplifier noise is typical 100nV/√Hz (33μVRMS over
the 10Hz to 100kHz bandwidth). The error amplifier’s noise
is RMS summed with the other noise terms to give a final
noise figure for the regulator.
Curves in the Typical Performance Characteristics section show noise spectral density and peak-to-peak noise
characteristics for both the reference current and error
amplifier over the 10Hz to 100kHz bandwidth.
Load Regulation
The LT3082 is a floating device. No ground pin exists on
the packages. Thus, the IC delivers all quiescent current
and drive current to the load. Therefore, it is not possible
to provide true remote load sensing. The connection resistance between the regulator and the load determines load
regulation performance. The data sheet’s load regulation
specification is Kelvin sensed at the package’s pins. Negative-side sensing is a true Kelvin connection by returning
the bottom of the voltage setting resistor to the negative
side of the load (see Figure 6).
Connected as shown, system load regulation is the sum
of the LT3082’s load regulation and the parasitic line
resistance multiplied by the output current. To minimize
load regulation, keep the positive connection between the
regulator and load as short as possible. If possible, use
large diameter wire or wide PC board traces.
LT3082
IN
10μA
+
–
PARASITIC
RESISTANCE
SET
OUT
RSET
RP
RP
LOAD
3082 F06
RP
Figure 6. Connections for Best Load Regulation
Thermal Considerations
The LT3082’s internal power and thermal limiting circuitry
protects itself under overload conditions. For continuous
normal load conditions, do not exceed the 125°C maximum
junction temperature. Carefully consider all sources of
thermal resistance from junction-to-ambient. This includes
(but is not limited to) junction-to-case, case-to-heat sink
interface, heat sink resistance or circuit board-to-ambient
as the application dictates. Consider all additional, adjacent
heat generating sources in proximity on the PCB.
Surface mount packages provide the necessary heatsinking
by using the heat spreading capabilities of the PC board,
copper traces and planes. Surface mount heat sinks, plated
through-holes and solder-filled vias can also spread the
heat generated by power devices.
Junction-to-case thermal resistance is specified from
the IC junction to the bottom of the case directly, or
the bottom of the pin most directly, in the heat path.
This is the lowest thermal resistance path for heat flow.
Only proper device mounting ensures the best possible
thermal flow from this area of the package to the heat
sinking material.
Note that the Exposed Pad of the DFN package and the
tab of the SOT-223 package is electrically connected to
the output (VOUT).
3082f
12
LT3082
APPLICATIONS INFORMATION
Tables 3 through 5 list thermal resistance as a function
of copper areas in a fixed board size. All measurements
were taken in still air on a 4-layer FR-4 board with 1oz
solid internal planes and 2oz external trace planes with a
total finished board thickness of 1.6mm.
Table 3. DD Package, 8-Lead DFN
COPPER AREA
TOPSIDE*
BACKSIDE
BOARD AREA
THERMAL RESISTANCE
(JUNCTION-TO-AMBIENT)
2500mm2
2500mm2
2500mm2
25°C/W
1000mm2
2500mm2
2500mm2
25°C/W
225mm2
2500mm2
2500mm2
28°C/W
100mm2
2500mm2
2500mm2
32°C/W
*Device is mounted on topside
Table 4. TS8 Package, 8-Lead SOT-23
COPPER AREA
PCB layers, copper weight, board layout and thermal vias
affect the resultant thermal resistance. Please reference
JEDEC standard JESD51-7 for further information on high
thermal conductivity test boards. Achieving low thermal
resistance necessitates attention to detail and careful layout.
Demo circuit 1447A’s board layout using multiple inner
VOUT planes and multiple thermal vias achieves 28°C/W
performance for the DFN package.
Calculating Junction Temperature
Example: Given an industrial factory application with an
input voltage of 15V ±10%, an output voltage of 12V ±5%,
an output current of 200mA and a maximum ambient
temperature of 50°C, what would be the maximum junction temperature for a DFN package?
The total circuit power equals:
TOPSIDE*
BACKSIDE
BOARD AREA
THERMAL RESISTANCE
(JUNCTION-TO-AMBIENT)
2500mm2
2500mm2
2500mm2
54°C/W
1000mm2
2500mm2
2500mm2
54°C/W
225mm2
2500mm2
2500mm2
57°C/W
VIN(MAX CONTINUOUS) = 16.5 (15V + 10%)
100mm2
2500mm2
2500mm2
63°C/W
VOUT(MIN CONTINUOUS) = 11.4V (12V – 5%)
*Device is mounted on topside
PTOTAL = (VIN – VOUT)(IOUT)
The SET pin current is negligible and can be ignored.
IOUT = 200mA
Table 5. ST Package, 3-Lead SOT-223
COPPER AREA
Power dissipation under these conditions equals:
TOPSIDE*
BACKSIDE
BOARD AREA
THERMAL RESISTANCE
(JUNCTION-TO-AMBIENT)
2500mm2
2500mm2
2500mm2
20°C/W
1000mm2
2500mm2
2500mm2
20°C/W
225mm2
2500mm2
2500mm2
24°C/W
100mm2
2500mm2
2500mm2
29°C/W
*Device is mounted on topside
For further information on thermal resistance and using thermal information,
refer to JEDEC standard JESD51, notably JESD51-12.
PTOTAL = (16.5 – 11.4V)(200mA) = 1.02W
Junction temperature equals:
TJ = TA + PTOTAL • θJA
TJ = 50°C + (1.02W • 30°C/W) = 80.6°C
In this example, junction temperature is below the maximum rating, ensuring reliable operation.
3082f
13
LT3082
APPLICATIONS INFORMATION
Protection Features
greater than IN, is less than 1mA (typically under 100μA),
protecting the LT3082 and sensitive loads.
The LT3082 incorporates several protection features ideal
for battery-powered circuits, among other applications. In
addition to normal monolithic regulator protection features
such as current limiting and thermal limiting, the LT3082
protects itself against reverse-input voltages, reverseoutput voltages, and reverse OUT-to-SET pin voltages.
Clamping diodes and 1k limiting resistors protect the
LT3082’s SET pin relative to the OUT pin voltage. These
protection components typically only carry current under
transient overload conditions. These devices are sized to
handle ±10V differential voltages and ±15mA crosspin
current flow without concern. Relative to these application
concerns, note the following two scenarios. The first scenario employs a noise-reducing SET pin bypass capacitor
while OUT is instantaneously shorted to GND. The second
scenario follows improper shutdown techniques in which
the SET pin is reset to GND quickly while OUT is held up
by a large output capacitance with light load. The Typical
Applications section shows simple, robust techniques for
shutting down SET and OUT together.
Current limit protection and thermal overload protection
protect the IC against output current overload conditions.
For normal operation, do not exceed a junction temperature
of 125°C. The thermal shutdown circuit’s temperature
threshold is typically 165°C and incorporates about 5°C
of hysteresis.
The LT3082’s IN pin withstands ±40V voltages with respect
to the OUT and SET pins. Reverse current flow, if OUT is
TYPICAL APPLICATIONS
DAC-Controlled Regulator
VIN
Two-Level Regulator
LT3082
IN
VIN
10μA
SPI
LTC2641
150k
450k
150k
–
+
LT3082
IN
10μA
+
–
LT1991
SET
+
–
OUT
VOUT
SET
4.7μF
R2
3082 TA02
GAIN = 4
OUT
VOUT
2.2μF
3082 TA03
VN2222LL
R1
3082f
14
LT3082
TYPICAL APPLICATIONS
Using a Lower Value SET Resistor
VIN
12V
LT3082
IN
10μA
+
–
C1
1μF
VOUT
0.5V TO 10V
VOUT = 0.5V + 1mA • RSET
OUT
SET
R1
49.9k
1%
1mA
R2
499Ω
1%
COUT
4.7μF
RSET
10k
3082 TA04
Adding Soft-Start
LT3082
IN
VIN
4.8V to 40V
10μA
+
–
D1
1N4148
C1
1μF
C2
0.01μF
VOUT
3.3V
0.2A
OUT
SET
COUT
4.7μF
R1
332k
3082 TA05
Coincident Tracking
LT3082
IN
10μA
IN
LT3082
+
–
10μA
VIN
7V TO 40V
LT3082
IN
+
–
10μA
C1
1.5μF
+
–
SET
R1
249k
R2
80.6k
OUT
C2
4.7μF
R3
169k
OUT
SET
OUT
SET
C3
4.7μF
VOUT3
5V
0.2A
C4
4.7μF
VOUT2
3.3V
0.2A
3082 TA06
VOUT1
2.5V
0.2A
3082f
15
LT3082
TYPICAL APPLICATIONS
Adding Shutdown
VIN
Reference Buffer
LT3082
IN
LT3082
IN
VIN
10μA
10μA
+
–
+
–
OUT
SET
ON OFF
Q1
VN2222LL
INPUT
OUTPUT
LT1019
Q2*
VN2222LL
R1
GND
SHUTDOWN
OUT
SET
VOUT
C1
1μF
3082 TA07
VOUT*
C2
4.7μF
* MINIMUM LOAD 0.5mA
3082 TA08
*Q2 INSURES ZERO OUTPUT
IN THE ABSENCE OF ANY
OUTPUT LOAD.
High Voltage Regulator
6.1V
10k
VIN
50V
1N4148
LT3082
IN
BUZ11
10μA
+
+
–
10μF
+
RSET
2MEG
15μF
VOUT
0.2A
OUT
SET
VOUT = 20V
VOUT = 10μA • RSET
4.7μF
3082 TA09
Ramp Generator
LT3082
IN
VIN
5V
10μA
+
–
1μF
SET
VN2222LL
1nF
OUT
VN2222LL
VOUT
4.7μF
3082 TA10
3082f
16
LT3082
PACKAGE DESCRIPTION
DD Package
8-Lead Plastic DFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1698)
0.675 ±0.05
3.5 ±0.05
1.65 ±0.05
2.15 ±0.05 (2 SIDES)
PACKAGE
OUTLINE
0.25 ± 0.05
0.50
BSC
2.38 ±0.05
(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
R = 0.115
TYP
5
3.00 ±0.10
(4 SIDES)
0.38 ± 0.10
8
1.65 ± 0.10
(2 SIDES)
PIN 1
TOP MARK
(NOTE 6)
(DD) DFN 1203
0.200 REF
0.75 ±0.05
0.00 – 0.05
4
0.25 ± 0.05
1
0.50 BSC
2.38 ±0.10
(2 SIDES)
BOTTOM VIEW—EXPOSED PAD
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON TOP AND BOTTOM OF PACKAGE
3082f
17
LT3082
PACKAGE DESCRIPTION
ST Package
3-Lead Plastic SOT-223
(Reference LTC DWG # 05-08-1630)
.248 – .264
(6.30 – 6.71)
.129 MAX
.114 – .124
(2.90 – 3.15)
.059 MAX
.264 – .287
(6.70 – 7.30)
.248 BSC
.130 – .146
(3.30 – 3.71)
.039 MAX
.059 MAX
.181 MAX
.033 – .041
(0.84 – 1.04)
.0905
(2.30)
BSC
.090
BSC
RECOMMENDED SOLDER PAD LAYOUT
10° – 16°
.010 – .014
(0.25 – 0.36)
10°
MAX
.071
(1.80)
MAX
10° – 16°
.024 – .033
(0.60 – 0.84)
.181
(4.60)
BSC
.012
(0.31)
MIN
.0008 – .0040
(0.0203 – 0.1016)
ST3 (SOT-233) 0502
3082f
18
LT3082
PACKAGE DESCRIPTION
TS8 Package
8-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1637)
0.52
MAX
2.90 BSC
(NOTE 4)
0.65
REF
1.22 REF
1.4 MIN
3.85 MAX 2.62 REF
2.80 BSC
1.50 – 1.75
(NOTE 4)
PIN ONE ID
RECOMMENDED SOLDER PAD LAYOUT
PER IPC CALCULATOR
0.22 – 0.36
8 PLCS (NOTE 3)
0.65 BSC
0.80 – 0.90
0.20 BSC
0.01 – 0.10
1.00 MAX
DATUM ‘A’
0.30 – 0.50 REF
0.09 – 0.20
(NOTE 3)
1.95 BSC
TS8 TSOT-23 0802
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DRAWING NOT TO SCALE
3. DIMENSIONS ARE INCLUSIVE OF PLATING
4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
5. MOLD FLASH SHALL NOT EXCEED 0.254mm
6. JEDEC PACKAGE REFERENCE IS MO-193
3082f
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
19
LT3082
TYPICAL APPLICATIONS
Active-Driven Regulator
VIN
LT3082
IN
10μA
+
–
OUT
V1
0V TO 5V
SET
R1, 100k
R2
100k
2.2μF
⎛ R2 ⎞
VOUT = ⎜
• V1 + 10µA • (R1 || R2)
⎝ R1 + R2 ⎟⎠
VOUT
0.5V TO 3V
3082 TA11
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1761
100mA, Low Noise LDO
300mV Dropout Voltage, Low Noise = 20μVRMS, VIN: 1.8V to 20V, ThinSOT™ Package
LT1762
150mA, Low Noise LDO
300mV Dropout Voltage, Low Noise = 20μVRMS, VIN: 1.8V to 20V, MS-8 Package
LT1763
500mA, Low Noise LDO
300mV Dropout Voltage, Low Noise = 20μVRMS, VIN: 1.8V to 20V, SO-8 Package
LT1962
300mA, Low Noise LDO
270mV Dropout Voltage, Low Noise = 20μVRMS, VIN: 1.8V to 20V, MS-8 Package
LT1964
200mA, Low Noise, Negative LDO
340mV Dropout Voltage, Low Noise = 30μVRMS, VIN: –1.8V to –20V, ThinSOT Package
LT3008
20mA, 45V, 3μA IQ Micropower
LDO
280mV Dropout Voltage, Low IQ = 3μA, VIN: 2V to 45V, VOUT : 0.6V to 39.5V;
ThinSOT and 2mm × 2mm DFN-6 Packages
LT3009
20mA, 3μA IQ Micropower LDO
280mV Dropout Voltage, Low IQ = 3μA, VIN: 1.6V to 20V, VOUT : 0.6V to 19.5V;
ThinSOT and SC-70 Packages
LT3010
50mA, High Voltage, Micropower
LDO
VIN: 3V to 80V, VOUT : 1.275V to 60V, VDO = 0.3V, IQ = 30μA, ISD <1μA,
Low Noise <100μVRMS, Stable with 1μF Output Capacitor, Exposed MS8 Package
LT3011
50mA, High Voltage, Micropower
LDO with Power Good
VIN: 3V to 80V, VOUT : 1.275V to 60V, VDO = 0.3V, IQ = 46μA, ISD <1μA,
Low Noise <100μVRMS, Power Good, Stable with 1μF Output Capacitor,
3mm × 3mm DFN-10 and Exposed MS-12E Packages
LT3012
250mA, 4V to 80V, Low Dropout
Micropower Linear Regulator
VIN: 4V to 80V, VOUT : 1.24V to 60V, VDO = 0.4V, IQ = 40μA, ISD <1μA,
TSSOP-16E and 4mm × 3mm DFN-12 Packages
LT3013
250mA, 4V to 80V, Low Dropout
Micro-power Linear Regulator
with PWRGD
VIN: 4V to 80V, VOUT : 1.24V to 60V, VDO = 0.4V, IQ = 65μA, ISD <1μA, Power Good;
TSSOP-16E and 4mm × 3mm DFN-12 Packages
LT3014/LT3014HV
20mA, 3V to 80V, Low Dropout
Micropower Linear Regulator
VIN: 3V to 80V (100V for 2ms, HV Version), VOUT : 1.22V to 60V, VDO = 0.35V, IQ = 7μA,
ISD <1μA, ThinSOT and 3mm × 3mm DFN-8 Packages
LT3020
100mA, Low Voltage VLDO Linear
Regulator
VIN: 0.9V to 10V, VOUT : 0.2V to 5V (Min), VDO = 0.15V, IQ = 120μA, Noise <250μVRMS,
Stable with 2.2μF Ceramic Capacitors, DFN-8 and MS-8 Packages
LT3021
500mA, Low Voltage, Very Low
Dropout VLDO Linear Regulator
VIN: 0.9V to 10V, Dropout Voltage = 160mV (Typical), Adjustable Output (VREF = VOUT(MIN)
= 200mV), Fixed Output Voltages: 1.2V, 1.5V, 1.8V, Stable with Low ESR, Ceramic Output
Capacitors 16-Pin 5mm × 5mm DFN and 8-Lead SO Packages
LT3080/LT3080-1
1.1A, Parallelable, Low Noise,
Low Dropout Linear Regulator
300mV Dropout Voltage (2-Supply Operation), Low Noise = 40μVRMS, VIN: 1.2V to 36V,
VOUT : 0V to 35.7V, Current-Based Reference with 1-Resistor VOUT Set; Directly Parallelable
(No Op Amp Required), Stable with Ceramic Capacitors; TO-220, SOT-223, MSOP-8 and
3mm × 3mm DFN-8 Packages; LT3080-1 Version Has Integrated Internal Ballast Resistor
LT3085
500mA, Parallelable, Low Noise,
Low Dropout Linear Regulator
275mV Dropout Voltage (2-Supply Operation), Low Noise: 40μVRMS, VIN: 1.2V to 36V,
VOUT: 0V to 35.7V, Current-Based Reference with 1-Resistor VOUT Set; Directly Parallelable (No
Op Amp Required), Stable with Ceramic Capacitors; MSOP-8 and 2mm × 3mm DFN-6 Packages
ThinSOT is a trademark of Linear Technology Corporation.
3082f
20 Linear Technology Corporation
LT 0709 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
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© LINEAR TECHNOLOGY CORPORATION 2009