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LM34
SNIS161D – MARCH 2000 – REVISED JANUARY 2016
LM34 Precision Fahrenheit Temperature Sensors
1 Features
3 Description
•
•
•
•
•
•
•
•
•
•
•
The LM34 series devices are precision integratedcircuit temperature sensors, whose output voltage is
linearly proportional to the Fahrenheit temperature.
The LM34 device has an advantage over linear
temperature sensors calibrated in degrees Kelvin,
because the user is not required to subtract a large
constant voltage from its output to obtain convenient
Fahrenheit scaling. The LM34 device does not
require any external calibration or trimming to provide
typical accuracies of ±1/2°F at room temperature and
±1-1⁄2°F over a full −50°F to 300°F temperature
range. Lower cost is assured by trimming and
calibration at the wafer level. The low output
impedance, linear output, and precise inherent
calibration of the LM34 device makes interfacing to
readout or control circuitry especially easy. It can be
used with single power supplies or with plus and
minus supplies. Because the LM34 device draws only
75 µA from its supply, the device has very low selfheating, less than 0.2°F in still air.
1
Calibrated Directly in Degrees Fahrenheit
Linear 10.0 mV/°F Scale Factor
1.0°F Accuracy Assured (at 77°F)
Rated for Full −50° to 300°F Range
Suitable for Remote Applications
Low Cost Due to Wafer-Level Trimming
Operates From 5 to 30 Volts
Less Than 90-μA Current Drain
Low Self-Heating, 0.18°F in Still Air
Nonlinearity Only ±0.5°F Typical
Low-Impedance Output, 0.4 Ω for 1-mA Load
2 Applications
•
•
•
•
Power Supplies
Battery Management
HVAC
Appliances
The LM34 device is rated to operate over a −50°F to
300°F temperature range, while the LM34C is rated
for a −40°F to 230°F range (0°F with improved
accuracy). The LM34 devices are series is available
packaged in hermetic TO-46 transistor packages;
while the LM34C, LM34CA, and LM34D are available
in the plastic TO-92 transistor package. The LM34D
device is available in an 8-lead, surface-mount, smalloutline package. The LM34 device is a complement
to the LM35 device (Centigrade) temperature sensor.
Device Information(1)
PART NUMBER
LM34
PACKAGE
BODY SIZE (NOM)
SOIC (8)
4.90 mm × 3.91 mm
TO-92 (3)
4.30 mm × 4.30 mm
TO-46 (3)
4.699 mm × 4.699 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Basic Fahrenheit Temperature Sensor (5°F to
300°F)
Full-Range Fahrenheit Temperature Sensor
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
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SNIS161D – MARCH 2000 – REVISED JANUARY 2016
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Table of Contents
1
2
3
4
5
6
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
4
4
4
4
5
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics: LM34A and LM34CA .......
Electrical Characteristics: LM34, LM34C, and
LM34D........................................................................
6.7 Typical Characteristics ..............................................
7
7
9
Detailed Description ............................................ 11
7.1 Overview ................................................................. 11
7.2 Functional Block Diagram ....................................... 11
7.3 Feature Description................................................. 11
7.4 Device Functional Modes........................................ 12
8
Application and Implementation ........................ 13
8.1 Application Information............................................ 13
8.2 Typical Application .................................................. 13
8.3 System Examples ................................................... 14
9 Power Supply Recommendations...................... 16
10 Layout................................................................... 16
10.1 Layout Guidelines ................................................. 16
10.2 Layout Example .................................................... 17
11 Device and Documentation Support ................. 18
11.1 Trademarks ........................................................... 18
11.2 Electrostatic Discharge Caution ............................ 18
11.3 Glossary ................................................................ 18
12 Mechanical, Packaging, and Orderable
Information ........................................................... 18
4 Revision History
Changes from Revision C (January 2015) to Revision D
•
Changed NDV Package (TO-46) pinout from Top View to Bottom View ............................................................................... 3
Changes from Revision B (November 2000) to Revision C
•
2
Page
Page
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation
section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and
Mechanical, Packaging, and Orderable Information section. ................................................................................................. 1
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5 Pin Configuration and Functions
NDV Package
3-PIn TO-46
(Bottom View)
+VS
VOUT
GND
t
Case is connected to negative pin (GND)
D Package
8-PIn SO8
(Top View)
VOUT
N.C.
1
2
8
7
+VS
N.C.
N.C.
3
6
N.C.
GND
4
5
N.C.
N.C. = No connection
LP Package
3-Pin TO-92
(Bottom View)
+VS VOUT GND
Pin Functions
PIN
NAME
TYPE
TO46/NDV
TO92/LP
SO8/D
+VS
—
—
8
POWER
VOUT
—
—
1
O
GND
—
—
4
GND
DESCRIPTION
Positive power supply pin
Temperature Sensor Analog Output
Device ground pin, connect to power supply negative terminal
2
3
N.C.
—
—
5
—
No Connection
6
7
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6 Specifications
6.1 Absolute Maximum Ratings (1) (2)
over operating free-air temperature range (unless otherwise noted)
MIN
MAX
UNIT
Supply voltage
35
–0.2
V
Output voltage
6
–1
V
10
mA
Output current
Storage temperature, Tstg
(1)
(2)
TO-46 Package
−76
356
TO-92 Package
−76
300
SO-8 Package
−65
150
°F
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
6.2 ESD Ratings
V(ESD)
(1)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)
VALUE
UNIT
±2500
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
Specified operating temperature range
(TMIN ≤ TA ≤ TMAX)
MIN
MAX
LM34, LM34A
–50
300
LM34C, LM34CA
–40
230
32
212
4
30
NDV (TO-46)
LP (TO-92)
D (SO8)
3 PINS
3 PINS
8 PINS
LM34D
Supply Voltage Range (+VS)
UNIT
°F
V
6.4 Thermal Information
LM34
THERMAL METRIC
(1)
RθJA
Junction-to-ambient thermal resistance
720
324
400
RθJC
Junction-to-case thermal resistance
43
—
—
(1)
4
UNIT
°F/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
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6.5 Electrical Characteristics: LM34A and LM34CA
Unless otherwise noted, these specifications apply: −50°F ≤ TJ ≤ 300°F for the LM34 and LM34A; −40°F ≤ TJ ≤ 230°F for the
LM34C and LM34CA; and 32°F ≤ TJ ≤ 212°F for the LM34D. VS = 5 Vdc and ILOAD = 50 µA in the circuit of Full-Range
Fahrenheit Temperature Sensor; 6 Vdc for LM34 and LM34A for 230°F ≤ TJ ≤ 300°F. These specifications also apply from
5°F to TMAX in the circuit of Basic Fahrenheit Temperature Sensor (5°F to 300°F).
PARAMETER
TEST CONDITIONS
Tested Limit (2)
TA = 77°F
LM34A
MIN
TYP
–1
LM34CA
MAX
MIN
1
–1
TYP
MAX
UNIT
1
Design Limit (3)
°F
±0.4
±0.4
Tested Limit
T A = 0°F
Accuracy
Design Limit
–2
±0.6
(1)
Tested Limit
TA = TMAX
–2
2
–2
Tested Limit
°F
2
Design Limit
°F
±0.8
TA = TMIN
2
±0.6
–2
±0.8
2
Design Limit
–3
±0.8
3
°F
0.6
°F
10.1
mV/°F
±0.8
Tested Limit
Nonlinearity
(4)
Design Limit
–0.7
TA = 77°F
Tested Limit
Sensor gain (Average
Slope)
0.7
9.9
±0.3
10.1
Design Limit
+9.9
TA = 77°F
+10
Tested Limit
TA = 77°F
0 ≤ IL ≤ 1 mA
–0.6
±0.35
–1
10
1
–1
mV/mA
±0.4
Load regulation (5)
±0.4
Tested Limit
0 ≤ IL ≤ 1 mA
Design Limit
–3
3
–3
±0.5
Tested Limit
TA = 77°F
5 V ≤ VS ≤ 30 V
Line regulation
–0.05
0.05
(4)
(5)
–0.05
mV/mA
0.05
mV/V
±0.01
±0.01
Tested Limit
Design Limit
–0.1
0.1
±0.02
(2)
(3)
3
±0.5
Design Limit
(5)
5 V ≤ VS ≤ 30 V
(1)
1
Design Limit
–0.1
0.1
mV/V
±0.02
Accuracy is defined as the error between the output voltage and 10 mV/°F times the device’s case temperature at specified conditions of
voltage, current, and temperature (expressed in °F).
Tested limits are specified and 100% tested in production.
Design limits are specified (but not 100% production tested) over the indicated temperature and supply voltage ranges. These limits are
not used to calculate outgoing quality levels.
Nonlinearity is defined as the deviation of the output-voltage-versus-temperature curve from the best-fit straight line over the rated
temperature range of the device.
Regulation is measured at constant junction temperature using pulse testing with a low duty cycle. Changes in output due to heating
effects can be computed by multiplying the internal dissipation by the thermal resistance.
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Electrical Characteristics: LM34A and LM34CA (continued)
Unless otherwise noted, these specifications apply: −50°F ≤ TJ ≤ 300°F for the LM34 and LM34A; −40°F ≤ TJ ≤ 230°F for the
LM34C and LM34CA; and 32°F ≤ TJ ≤ 212°F for the LM34D. VS = 5 Vdc and ILOAD = 50 µA in the circuit of Full-Range
Fahrenheit Temperature Sensor; 6 Vdc for LM34 and LM34A for 230°F ≤ TJ ≤ 300°F. These specifications also apply from
5°F to TMAX in the circuit of Basic Fahrenheit Temperature Sensor (5°F to 300°F).
PARAMETER
TEST CONDITIONS
LM34A
MIN
TYP
Tested Limit
VS = 5 V, TA = 77°F
LM34CA
MAX
MIN
TYP
90
MAX
UNIT
90
Design Limit
µA
75
75
Tested Limit
VS = 5 V
Quiescent current
Design Limit
160
131
(6)
Tested Limit
VS = 30 V, TA = 77°F
139
µA
116
92
92
Design Limit
µA
76
76
Tested Limit
VS = 30 V
Design Limit
163
132
Tested Limit
4 V ≤ VS ≤ 30 V, TA = 77°F
2
µA
2
Design Limit
µA
0.5
Change of quiescent
current (5)
142
117
0.5
Tested Limit
5 V ≤ VS ≤ 30 V
Design Limit
3
1
3
µA
1
Tested Limit
Temperature coefficient
of quiescent current
Design Limit
0.5
0.3
In circuit of Basic Fahrenheit
Minimum temperature for Temperature Sensor (5°F to
rated accuracy
300°F), IL = 0
TA = 77°F
Long-term stability
(6)
6
0.5
µA/°F
0.3
Tested Limit
Design Limit
TJ = TMAX for 1000 hours
5
5
3
3
±0.16
±0.16
°F
°F
Quiescent current is defined in the circuit of Basic Fahrenheit Temperature Sensor (5°F to 300°F).
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6.6 Electrical Characteristics: LM34, LM34C, and LM34D
Unless otherwise noted, these specifications apply: −50°F ≤ TJ ≤ 300°F for the LM34 and LM34A; −40°F ≤ TJ ≤ 230°F for the
LM34C and LM34CA; and +32°F ≤ TJ ≤ 212°F for the LM34D. VS = 5 Vdc and ILOAD = 50 µA in the circuit of Full-Range
Fahrenheit Temperature Sensor; 6 Vdc for LM34 and LM34A for 230°F ≤ TJ ≤ 300°F. These specifications also apply from
5°F to TMAX in the circuit of Basic Fahrenheit Temperature Sensor (5°F to 300°F).
PARAMETER
CONDITIONS
Tested Limit (2)
TA = 77°F
LM34
MIN
TYP
–2
LM34C, LM34D
MAX
MIN
2
–2
TYP
MAX
UNIT
2
Design Limit (3)
°F
±0.8
±0.8
Tested Limit
TA = 0°F
Design Limit
–3
±1
Accuracy, LM34,
LM34C (1)
Tested Limit
TA = TMAX
–3
3
°F
3
°F
4
°F
±1
3
Design Limit
–3
±1.6
±1.6
Tested Limit
TA = TMIN
Design Limit
–3
3
–4
±1.6
±1.6
Tested Limit
TA = 77°F
–3
3
Design Limit
°F
±1.2
Tested Limit
Accuracy, LM34D (1)
TA = TMAX
Design Limit
–4
4
°F
4
°F
1
°F
±1.8
Tested Limit
TA = TMIN
Design Limit
–4
±1.8
Tested Limit
Nonlinearity
(4)
Design Limit
–1.0
1
–1
±0.6
Tested Limit
Sensor gain (Average
Slope)
9.8
±0.4
10.2
Design Limit
9.8
10
TA = 77°F
0 ≤ IL ≤ 1 mA
Tested Limit
–2.5
2.5
–2.5
mV/mA
±0.4
Tested Limit
TMIN ≤ TA ≤ 150°F
0 ≤ IL ≤ 1 mA
Design Limit
–6.0
6
–6
±0.5
Tested Limit
TA = 77°F,
5 V ≤ VS ≤ 30 V
–0.1
0.1
(5)
–0.1
0.1
Design Limit
mV/V
Design Limit
–0.2
±0.01
0.2
±0.02
(4)
mV/mA
Tested Limit
5 V ≤ VS ≤ 30 V
(2)
(3)
6
±0.5
±0.01
Line regulation (5)
(1)
mV/°F
2.5
Design Limit
±0.4
Load regulation (5)
10.2
10
–0.2
0.2
mV/V
±0.02
Accuracy is defined as the error between the output voltage and 10 mV/˚F times the device’s case temperature at specified conditions of
voltage, current, and temperature (expressed in ˚F).
Tested limits are specified and 100% tested in production.
Design limits are specified (but not 100% production tested) over the indicated temperature and supply voltage ranges. These limits are
not used to calculate outgoing quality levels.
Nonlinearity is defined as the deviation of the output-voltage-versus-temperature curve from the best-fit straight line over the rated
temperature range of the device.
Regulation is measured at constant junction temperature using pulse testing with a low duty cycle. Changes in output due to heating
effects can be computed by multiplying the internal dissipation by the thermal resistance.
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Electrical Characteristics: LM34, LM34C, and LM34D (continued)
Unless otherwise noted, these specifications apply: −50°F ≤ TJ ≤ 300°F for the LM34 and LM34A; −40°F ≤ TJ ≤ 230°F for the
LM34C and LM34CA; and +32°F ≤ TJ ≤ 212°F for the LM34D. VS = 5 Vdc and ILOAD = 50 µA in the circuit of Full-Range
Fahrenheit Temperature Sensor; 6 Vdc for LM34 and LM34A for 230°F ≤ TJ ≤ 300°F. These specifications also apply from
5°F to TMAX in the circuit of Basic Fahrenheit Temperature Sensor (5°F to 300°F).
PARAMETER
CONDITIONS
LM34
MIN
TYP
Tested Limit
VS = 5 V, TA = 77°F
LM34C, LM34D
MAX
MIN
TYP
100
MAX
UNIT
100
Design Limit
µA
75
75
Tested Limit
VS = 5 V
Quiescent current
Design Limit
176
131
(6)
Tested Limit
VS = 30 V, TA = 77°F
154
µA
116
103
103
Design Limit
µA
76
76
Tested Limit
VS = 30 V
Design Limit
181
132
Tested Limit
4 V ≤ VS ≤ 30 V,
TA = +77°F
3
µA
3
Design Limit
µA
0.5
Change of quiescent
current (5)
159
117
0.5
Tested Limit
5 V ≤ VS ≤ 30 V
Design Limit
5
1
5
µA
1
Tested Limit
Temperature coefficient
of quiescent current
Design Limit
0.7
0.3
Minimum temperature
for rated accuracy
Long-term stability
(6)
8
In circuit of Basic
Fahrenheit
Temperature Sensor
(5°F to 300°F), IL = 0
0.7
µA/°F
0.3
Tested Limit
Design Limit
TJ = TMAX for 1000 hours
5.0
5
3
3
±0.16
±0.16
°F
°F
Quiescent current is defined in the circuit of Basic Fahrenheit Temperature Sensor (5°F to 300°F).
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6.7 Typical Characteristics
Figure 1. Thermal Resistance Junction to Air
Figure 2. Thermal Time Constant
Figure 3. Thermal Response in Still Air
Figure 4. Thermal Response in Stirred Oil Bath
Figure 5. Minimum Supply Voltage vs Temperature
Figure 6. Quiescent Current vs Temperature (in Circuit of
Basic Fahrenheit Temperature Sensor (5°F to 300°F))
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Typical Characteristics (continued)
Figure 7. Quiescent Current vs Temperature
(in Circuit of Full-Range Fahrenheit Temperature Sensor;
−VS = −5V, R1 = 100k)
Figure 8. Accuracy vs Temperature (Specified)
Figure 10. Noise Voltage
Figure 9. Accuracy vs Temperature (Specified)
Figure 11. Start-Up Response
10
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7 Detailed Description
7.1 Overview
The LM34 series devices are precision integrated-circuit temperature sensors, whose output voltage is linearly
proportional to the Fahrenheit temperature. The LM34 device has an advantage over linear temperature sensors
calibrated in degrees Kelvin, because the user is not required to subtract a large constant voltage from its output
to obtain convenient Fahrenheit scaling. The LM34 device does not require any external calibration or trimming
to provide typical accuracies of ±1/2°F at room temperature and ±1-1⁄2°F over a full −50°F to 300°F temperature
range. Lower cost is assured by trimming and calibration at the wafer level. The low output impedance, linear
output, and precise inherent calibration of the LM34 device makes interfacing to readout or control circuitry
especially easy. It can be used with single power supplies or with plus and minus supplies. Because the LM34
device draws only 75 µA from its supply, the device has very low self-heating, less than 0.2°F in still air.
The temperature sensing element is comprised of a simple base emitter junction that is forward biased by a
current source. The temperature sensing element is buffered by an amplifier and provided to the OUT pin. The
amplifier has a simple class-A output stage thus providing a low impedance output that can source 16 μA and
sink 1 μA.
The temperature sensing element is comprised of a delta-VBE architecture. The temperature sensing element is
then buffered by an amplifier and provided to the VOUT pin. The amplifier has a simple class A output stage with
typical 0.5-Ω output impedance as shown in the Functional Block Diagram. Therefore, the LM34 device can only
source current and the sinking capability of the device is limited to 1 µA.
7.2 Functional Block Diagram
7.3 Feature Description
7.3.1 Capacitive Drive Capability
Like most micropower circuits, the LM34 device has a limited ability to drive heavy capacitive loads. The LM34
device, by itself, is able to drive 50 pF without special precautions. If heavier loads are anticipated, it is easy to
isolate or decouple the load with a resistor; see Figure 12. You can improve the tolerance of capacitance with a
series R-C damper from output to ground; see Figure 13. When the LM34 is applied with a 499-Ω load resistor
(as shown Figure 18 and Figure 19), the device is relatively immune to wiring capacitance because the
capacitance forms a bypass from ground to input, not on the output. However, as with any linear circuit
connected to wires in a hostile environment, its performance can be affected adversely by intense
electromagnetic sources such as relays, radio transmitters, motors with arcing brushes, transients of the SCR,
and so on, as the wiring of the device can act as a receiving antenna and the internal junctions can act as
rectifiers. For best results in such cases, a bypass capacitor from VIN to ground and a series R-C damper, such
as 75 Ω in series with 0.2 μF or 1 μF from output to ground, are often useful. See Figure 23, Figure 24 and
Figure 26 for more details.
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Feature Description (continued)
Figure 12. LM34 With Decoupling from Capacitive
Load
Figure 13. LM34 With R-C Damper
7.3.2 LM34 Transfer Function
The accuracy specifications of the LM34 devices are given with respect to a simple linear transfer function shown
in Equation 1:
VOUT = 10 mV/°F × T °F
where
•
•
VOUT is the LM34 output voltage
T is the temperature in °F
(1)
7.4 Device Functional Modes
The only functional mode of the LM34 device is that it has an analog output directly proportional to temperature.
12
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The features of the LM34 device make it suitable for many general temperature sensing applications. Multiple
package options expand on flexibility of the device.
8.2 Typical Application
8.2.1 Basic Fahrenheit Temperature Sensor Application
Figure 14. Basic Fahrenheit Temperature Sensor (5°F to 300°F)
8.2.1.1 Design Requirements
Table 1. Key Requirements
PARAMETER
VALUE
Accuracy at 77°F
±2°F
Accuracy from –50°F to 300°F
Temperature Slope
±3°F
10 mV/°F
8.2.1.2 Detailed Design Procedure
Because the LM34 is a simple temperature sensor that provides an analog output, design requirements related
to layout are more important than electrical requirements (see Layout).
8.2.1.3 Application Curve
Figure 15. Temperature Error
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8.3 System Examples
Figure 16. Full-Range Fahrenheit Temperature
Sensor
Figure 17. Full Range Farenheit Sensor (–50 °F to
300 °F)
VOUT = 10 mV/°F (TA+3°F) from 3°F to 100°F
Figure 18. Two-Wire Remote Temperature Sensor
(Grounded Sensor)
Figure 19. Two-Wire Remote Temperature Sensor
(Output Referred to Ground)
Figure 20. 4- to -20 mA Current Source (0°F to
100°F)
Figure 21. Fahrenheit Thermometer (Analog Meter)
14
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System Examples (continued)
Figure 22. Expanded Scale Thermometer
(50°F to 80°F, for Example Shown)
Figure 23. Temperature-to-Digital Converter
(Serial Output, 128°F Full Scale)
∗ = 1% or 2% film resistor
— Trim RB for VB = 3.525V
— Trim RC for VC = 2.725V
— Trim RA for VA = 0.085V + 40 mV/°F x TAMBIENT
— Example, VA = 3.285V at 80°F
Figure 24. LM34 With Voltage-to-Frequency
Converter and Isolated Output
(3°F to 300°F; 30 Hz to 3000 Hz)
Figure 25. Bar-Graph Temperature Display
(Dot Mode)
Figure 26. Temperature-to-Digital Converter
(Parallel TRI-STATE Outputs for Standard Data Bus
to µP Interface, 128°F Full Scale)
Figure 27. Temperature Controller
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9 Power Supply Recommendations
It may be necessary to add a bypass filter capacitor in noisy environments, as shown in as shown in Figure 13.
10 Layout
10.1 Layout Guidelines
The LM34 device can be easily applied in the same way as other integrated-circuit temperature sensors. The
device can be glued or cemented to a surface and its temperature will be within about 0.02°F of the surface
temperature. This presumes that the ambient air temperature is almost the same as the surface temperature; if
the air temperature were much higher or lower than the surface temperature, the actual temperature of the LM34
die would be at an intermediate temperature between the surface temperature and the air temperature. This is
especially true for the TO-92 plastic package, where the copper leads are the principal thermal path to carry heat
into the device, so its temperature might be closer to the air temperature than to the surface temperature.
To minimize this problem, be sure that the wiring to the LM34, as it leaves the device, is held at the same
temperature as the surface of interest. The easiest way to do this is to cover up these wires with a bead of
epoxy, which will insure that the leads and wires are all at the same temperature as the surface, and that the die
temperature of the LM34 device will not be affected by the air temperature.
The TO-46 metal package can be soldered to a metal surface or pipe without damage. In the case where
soldering is used, the V− terminal of the circuit will be grounded to that metal. Alternatively, the LM34 device can
be mounted inside a sealed-end metal tube, and can then be dipped into a bath or screwed into a threaded hole
in a tank. As with any IC, the LM34 and accompanying wiring and circuits must be kept insulated and dry, to
avoid leakage and corrosion. This is especially true if the circuit may operate at cold temperatures where
condensation can occur. Printed-circuit coatings and varnishes such as a conformal coating and epoxy paints or
dips are often used to insure that moisture cannot corrode the LM34 or its connections.
These devices are sometimes soldered to a small, light-weight heat fin to decrease the thermal time constant
and speed up the response in slowly-moving air. On the other hand, a small thermal mass may be added to the
sensor to give the steadiest reading despite small deviations in the air temperature.
Table 2. Temperature Rise of LM34 Due to Self-Heating (Thermal Resistance)
TO-46
NO HEAT SINK
TO-46,
SMALL HEAT
Fin (1)
TO-92,
NO HEAT SINK
TO-92,
SMALL HEAT
Fin (2)
SO-8
NO HEAT SINK
SO-8
SMALL HEAT Fin
Still air
720°F/W
180°F/W
324°F/W
252°F/W
400°F/W
200°F/W
Moving air
180°F/W
72°F/W
162°F/W
126°F/W
190°F/W
160°F/W
Still oil
180°F/W
72°F/W
162°F/W
126°F/W
—
—
Stirred oil
90°F/W
54°F/W
81°F/W
72°F/W
—
—
—
—
CONDITIONS
(Clamped to metal,
infinite heart sink)
(1)
(2)
16
(43°F/W )
(95°F/W )
Wakefield type 201 or 1-inch disc of 0.020-inch sheet brass, soldered to case, or similar.
TO-92 and SO-8 packages glued and leads soldered to 1-inch square of 1/16 inches printed circuit board with 2 oz copper foil, or
similar.
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LM34
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SNIS161D – MARCH 2000 – REVISED JANUARY 2016
10.2 Layout Example
VIA to ground plane
VIA to power plane
VOUT
+VS
N.C.
N.C.
N.C.
N.C.
GND
N.C.
0.01µ F
Figure 28. Layout Example
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11 Device and Documentation Support
11.1 Trademarks
All trademarks are the property of their respective owners.
11.2 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
11.3 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
18
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Product Folder Links: LM34
PACKAGE OPTION ADDENDUM
www.ti.com
30-Sep-2021
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LM34AH
ACTIVE
TO
NDV
3
500
Non-RoHS &
Non-Green
Call TI
Call TI
-45 to 148
( LM34AH, LM34AH)
LM34AH/NOPB
ACTIVE
TO
NDV
3
500
RoHS & Green
Call TI
Level-1-NA-UNLIM
-45 to 148
( LM34AH, LM34AH)
LM34CAH
ACTIVE
TO
NDV
3
500
Non-RoHS &
Non-Green
Call TI
Call TI
-40 to 110
( LM34CAH, LM34CAH
)
LM34CAH/NOPB
ACTIVE
TO
NDV
3
500
RoHS & Green
Call TI
Level-1-NA-UNLIM
-40 to 110
( LM34CAH, LM34CAH
)
LM34CAZ/NOPB
ACTIVE
TO-92
LP
3
1800
RoHS & Green
SN
N / A for Pkg Type
-40 to 110
LM34
CAZ
LM34CZ/NOPB
ACTIVE
TO-92
LP
3
1800
RoHS & Green
SN
N / A for Pkg Type
-40 to 110
LM34
CZ
LM34DH
ACTIVE
TO
NDV
3
1000
Non-RoHS &
Non-Green
Call TI
Call TI
0 to 100
( LM34DH, LM34DH)
LM34DH/NOPB
ACTIVE
TO
NDV
3
1000
RoHS & Green
Call TI
Level-1-NA-UNLIM
0 to 100
( LM34DH, LM34DH)
LM34DM
NRND
SOIC
D
8
95
Non-RoHS
& Green
Call TI
Level-1-235C-UNLIM
0 to 100
LM34D
M
LM34DM/NOPB
ACTIVE
SOIC
D
8
95
RoHS & Green
SN
Level-1-260C-UNLIM
0 to 100
LM34D
M
LM34DMX/NOPB
ACTIVE
SOIC
D
8
2500
RoHS & Green
SN
Level-1-260C-UNLIM
0 to 100
LM34D
M
LM34DZ/LFT7
ACTIVE
TO-92
LP
3
2000
RoHS & Green
SN
N / A for Pkg Type
LM34DZ/NOPB
ACTIVE
TO-92
LP
3
1800
RoHS & Green
SN
N / A for Pkg Type
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
Addendum-Page 1
LM34
DZ
0 to 100
LM34
DZ
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
30-Sep-2021
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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