Rainbow Electronics LM60 User Manual

LM60

2.7V, SOT-23 or TO-92 Temperature Sensor

General Description

The LM60 is a precision integrated-circuit temperature sen­sor that can sense a −40˚C to +125˚C temperature range
while operating from a single +2.7V supply. The LM60’s
output voltage is linearly proportional to Celsius (Centigrade)
temperature (+6.25 mV/˚C) and has a DC offset of +424 mV.
The offset allows reading negative temperatures without the
need for anegativesupply. The nominal output voltageofthe
LM60 ranges from +174 mV to +1205 mV for a −40˚C to
+125˚C temperature range. The LM60 is calibrated to pro­vide accuracies of
over the full −25˚C to +125˚C temperature range.

The LM60’s linear output, +424 mV offset, and factory cali­bration simplify external circuitry required in a single supply
environment where reading negative temperatures is re­quired. Because the LM60’s quiescent current is less than
110µA, self-heating is limited to a very low 0.1˚C in still air in
the SOT-23 package. Shutdown capability for the LM60 is
intrinsic because its inherent low power consumption allows
it to be powered directly from the output of many logic gates.

±

2.0˚C at room temperature and±3˚C

Features

n Calibrated linear scale factor of +6.25 mV/˚C
n Rated for full −40˚ to +125˚C range
n Suitable for remote applications

n Available in SOT-23 and TO-92 packages

Applications

n Cellular Phones
n Computers
n Power Supply Modules
n Battery Management
n FAX Machines
n Printers
n HVAC
n Disk Drives
n Appliances

Key Specifications

n Accuracy at 25˚C:
n Accuracy for −40˚C to +125˚C:
n Accuracy for −25˚C to +125˚C:
n Temperature Slope: +6.25mV/˚C
n Power Supply Voltage Range: +2.7V to +10V
n Current Drain
n Nonlinearity:
n Output Impedance: 800Ω (max)

±

2.0 and±3.0˚C (max)

@

25˚C: 110µA (max)

±

0.8˚C (max)

±

4.0˚C (max)

±

3.0˚C (max)

LM60 2.7V, SOT-23 or TO-92 Temperature Sensor

July 2001

Typical Application

VO= (+6.25 mV/˚C x T ˚C) + 424 mV

Temperature (T) Typical V

+125˚C +1205 mV
+100˚C +1049 mV

+25˚C +580 mV

0˚C +424 mV

−25˚C +268 mV

−40˚C +174 mV

FIGURE 1. Full-Range Centigrade Temperature Sensor

(−40˚C to +125˚C) Operating from a Single Li-Ion

Battery Cell

01268102

O

Connection Diagrams

SOT-23

01268101

Top View

See NS Package Number MA03B

TO-92

01268123

See NS Package Number Z03A

© 2001 National Semiconductor Corporation DS012681 www.national.com

Ordering Information

LM60

Order

Number

Device

Marking

Supplied In

LM60BIM3 T6B 1000 Units on Tape and Reel
LM60BIM3X T6B 3000 Units on Tape and Reel
LM60CIM3 T6C 1000 Units on Tape and Reel
LM60CIM3X T6C 3000 Units on Tape and Reel
LM60BIZ LM60BIZ Bulk

LM60CIZ LM60CIZ Bulk

Accuracy Over

Specified

Temperature

Range

±

3

±

4

±

3

±

4

Specified

Temperature

Range

−25˚C ≤ T

A

+125˚C

−40˚C ≤ T

A

+125˚C

−25˚C ≤ T

A

+125˚C

−40˚C ≤ T

A

+125˚C

≤

≤

≤

≤

Package Type

SOT-23

TO-92

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LM60

Absolute Maximum Ratings (Note 1)

Supply Voltage +12V to −0.2V
Output Voltage (+V

+ 0.6V) to

S

−0.6V

Storage Temperature −65˚C to

+150˚C

Maximum Junction Temperature

) +125˚C

(T

JMAX

Output Current 10 mA
Input Current at any pin (Note 2) 5 mA
ESD Susceptibility (Note 3) :

Human Body Model 2500V
Machine Model

SOT-23
TO-92

250V
200V

Recommended Lead Temperature
(Note 4):

SOT Package:

Vapor Phase (60 sec)
Infrared (15 sec)

TO-92 Package (3 sec, dwell time)

+215˚C
+220˚C
+240˚C

Operating Ratings(Note 1)

Specified Temperature Range: T

LM60B −25˚C ≤ TA≤ +125˚C

LM60C −40˚C ≤ T
Supply Voltage Range (+V
Thermal Resistance, θ

) +2.7V to +10V

S

(Note

JA

5)

SOT-23

TO-92

MIN

≤ TA≤ T

≤ +125˚C

A

450˚C/W
180˚C/W

MAX

Electrical Characteristics

Unless otherwise noted, these specifications apply for +VS= +3.0 VDCand I

=T

MIN

to T

; all other limits TA=TJ= 25˚C.

MAX

Parameter Conditions Typical

(Note 6)

Accuracy (Note 8)

Output Voltage at 0˚C +424 mV
Nonlinearity (Note 9)
Sensor Gain +6.25 +6.06 +6.00 mV/˚C (min)
(Average Slope) +6.44 +6.50 mV/˚C (max)
Output Impedance 800 800 Ω (max)
Line Regulation (Note 10) +3.0V ≤ +V

+2.7V ≤ +V

Quiescent Current +2.7V ≤ +V

Change of Quiescent Current +2.7V ≤ +V

≤ +10V

S

≤ +3.3V

S

≤ +10V 82 110 110 µA (max)

S

≤ +10V

S

±

5.0 µA (max)
Temperature Coefficient of 0.2 µA/˚C
Quiescent Current
Long Term Stability (Note 11) T

J=TMAX

=+125˚C, for

±

0.2 ˚C

1000 hours

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed
specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test
conditions.

Note 2: When the input voltage (V
Note 3: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200 pF capacitor discharged

directly into each pin.

Note 4: See the URL ”http://www.national.com/packaging/“ for other recomdations and methods of soldering surface mount devices.
Note 5: The junction to ambient thermal resistance (θ
Note 6: Typicals are at T
Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 8: Accuracy is defined as the error between theoutput voltage and +6.25 mV/˚C times the device’s case temperature plus 424 mV, at specified conditions of

voltage, current, and temperature (expressed in ˚C).
Note 9: Nonlinearity is defined as the deviation of the output-voltage-versus-temperature curve from the best-fit straight line, over the device’s rated temperature

range.

) at any pin exceeds power supplies (V

I

) is specified without a heat sink in still air.

= 25˚C and represent most likely parametric norm.

J=TA

JA

<

GND or V

I

>

+VS), the current at that pin should be limited to 5 mA.

I

= 1 µA. Boldface limits apply for TA=T

LOAD

LM60B LM60C Units

Limits Limits

(Note 7) (Note 7)

±

2.0

±

3.0

±

0.6

±

0.3

±

2.3

±

3.0 ˚C (max)

±

4.0 ˚C (max)

±

0.8 ˚C (max)

±

0.3 mV/V (max)

±

2.3 mV (max)

125 125 µA (max)

(Limit)

J

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Electrical Characteristics (Continued)

LM60

Note 10: 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.
Note 11: For best long-term stability, any precision circuit will give best results if the unit is aged at a warm temperature, and/or temperature cycled for at least 46

hours before long-term life test begins. This is especially true when a small (Surface-Mount) part is wave-soldered; allow time for stress relaxation to occur. The
majority of the drift will occur in the first 1000 hours at elevated temperatures. The drift after 1000 hours will not continue at the first 1000 hour rate.

Typical Performance Characteristics To generate these curves the LM60 was mounted to a

printed circuit board as shown in

Thermal Resistance

Junction to Air Thermal Time Constant

Thermal Response

in Stirred Oil Bath

with Heat Sink

Figure 2

.

Thermal Response in

Still Air with Heat Sink

01268103 01268104 01268105

Start-Up Voltage
vs. Temperature

Thermal Response in Still

Air without a Heat Sink

01268106

Quiescent Current

vs. Temperature Accuracy vs Temperature Noise Voltage

01268109 01268110

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01268107 01268108

01268111

Typical Performance Characteristics To generate these curves the LM60 was mounted to a

printed circuit board as shown in

Supply Voltage

vs Supply Current Start-Up Response

Figure 2

01268112

. (Continued)

01268122

LM60

FIGURE 2. Printed Circuit Board Used

for Heat Sink to Generate All Curves.

1

⁄2" Square Printed Circuit Board

with 2 oz. Copper Foil or Similar.

1.0 Mounting

The LM60 can be applied easily in the same way as other
integrated-circuit temperature sensors. It can be glued or
cemented to a surface. The temperature that the LM60 is
sensing will be within about +0.1˚C of the surface tempera­ture that LM60’s leads are attached to.

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 LM60 die would be at an interme­diate temperature between the surface temperature and the
air temperature.

To ensure good thermal conductivity the backside of the
LM60 die is directly attached to the GND pin. The lands and
traces to the LM60 will, of course, be part of the printed
circuit board, which is the object whose temperature is being
measured. These printed circuit board lands and traces will
not cause the LM60’s temperature to deviate from the de­sired temperature.

Alternatively, the LM60 can be mounted inside a sealed-end
metal tube, and can then be dipped into a bath or screwed

01268114

into a threaded hole in a tank. As with any IC, the LM60 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 Humiseal and epoxy paints or dips are often used to
ensure that moisture cannot corrode the LM60 or its connec­tions.

The thermal resistance junction to ambient (θ

)isthe

JA

parameter used to calculate the rise of a device junction
temperature due to the device power dissipation. For the
LM60 the equation used to calculate the rise in the die
temperature is as follows:

T

where I

J=TA+θJA

is the quiescent current and ILis the load current on

Q

[(+VSIQ) + (+VS−VO)IL]

the output.
The table shown in

Figure 3

summarizes the rise in die
temperature of the LM60 without any loading, and the ther­mal resistance for different conditions.

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1.0 Mounting (Continued)

LM60

SOT-23

*

SOT-23

**

TO-92

*

no heat sink small heat fin no heat fin small heat fin

θ

TJ−T

JA

θ

A

TJ−T

JA

θ

A

JA

TJ−T

A

(˚C/W) (˚C) (˚C/W) (˚C)

Still air 450 0.17 260 0.1 180 0.07 140 0.05
Moving air 180 0.07 90 0.034 70 0.026

*

-Part soldered to 30 gauge wire.

**

-Heat sink used is1⁄2" square printed circuit board with 2 oz. foil with part attached as shown in

***

-Part glued or leads soldered to 1” square of 1/16” printed circuit board with 2 oz. foil or similar.

FIGURE 3. Temperature Rise of LM60 Due to

Self-Heating and Thermal Resistance (θ

)

JA

2.0 Capacitive Loads

The LM60 handles capacitive loading well. Without any spe­cial precautions, the LM60 can drive any capacitive load as
shown in
LM60 has a maximum output impedance of 800Ω.Inan
extremely noisy environment it may be necessary to add
some filtering to minimize noise pickup. It is recommended
that 0.1 µF be added from +V
supply voltage, as shown in
it may be necessary to add a capacitor from the output to
ground.A 1 µF output capacitor with the 800Ω output imped­ance will form a 199 Hz lowpass filter.Since the thermal time
constant of the LM60 is much slower than the 6.3 ms time
constant formed by the RC, the overall response time of the
LM60 will not be significantly affected. For much larger ca­pacitors this additional time lag will increase the overall
response time of the LM60.

Figure 4

. Over the specified temperature range the

to GND to bypass the power

S

Figure 5

. In a noisy environment

FIGURE 4. LM60 No Decoupling Required for

Capacitive Load

TO-92

θ

JA

Figure 2

***

TJ−T

.

A

01268115

01268116

FIGURE 5. LM60 with Filter for Noisy Environment

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2.0 Capacitive Loads (Continued)

FIGURE 6. Simplified Schematic

LM60

01268117

3.0 Applications Circuits

01268118

FIGURE 7. Centigrade Thermostat

FIGURE 8. Conserving Power Dissipation with Shutdown

01268119

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Physical Dimensions inches (millimeters)

LM60

unless otherwise noted

SOT-23 Molded Small Outline Transistor Package (M3)

Order Number LM60BIM3 or LM60CIM3

NS Package Number MA03B

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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

LM60 2.7V, SOT-23 or TO-92 Temperature Sensor

TO-92 Molded Plastic Package (Z)

Order Number LM60BIZ or LM60CIZ

Package Number Z03A

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COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the

2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.

labeling, can be reasonably expected to result in a
significant injury to the user.

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