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LM60B/LM60C
2.7V, SOT-23 Temperature Sensor
Y
General Description
The LM60 is a precision integrated-circuit temperature sensor that can sense a
while operating from a single
output voltage is linearly proportional to Celsius (Centigrade) temperature (
a
424 mV. The offset allows reading negative temperatures
without the need for a negative supply. The nominal output
voltage of the LM60 ranges from
b
for a
40§Ctoa125§C temperature range. The LM60 is
calibrated to provide accuracies of
ature and
g
ture range.
The LM60’s linear output,
bration simplify external circuitry required in a single supply
environment where reading negative temperatures is required. Because the LM60’s quiescent current is less than
110 mA, self-heating is limited to a very low 0.1
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.
b
40§Ctoa125§C temperature range
a
2.7V supply. The LM60’s
a
6.25 mV/§C) and has a DC offset of
a
174 mV toa1205 mV
g
2.0§C at room temper-
3§C over the fullb25§Ctoa125§C tempera-
a
424 mV offset, and factory cali-
C in still air.
§
Applications
Y
Cellular Phones
Y
Computers
Power Supply Modules
Y
Battery Management
Y
FAX Machines
Y
Printers
Y
HVAC
Y
Disk Drives
Y
Appliances
Features
Y
Calibrated linear scale factor ofa6.25 mV/§C
Y
Rated for fullb40§toa125§C range
Y
Suitable for remote applications
Key Specifications
Y
Accuracy at 25§C
Y
Accuracy forb40§Ctoa125§C
Y
Accuracy forb25§Ctoa125§C
Y
Temperature Slope
Y
Power Supply Voltage Range
Y
Current Drain@25§C 110 mA (max)
Y
Nonlinearity
Y
Output Impedance 800X (max)
April 1996
g
2.0 andg3.0§C (max)
g
4.0§C (max)
g
3.0§C (max)
a
6.25 mV/§C
a
2.7V toa10V
g
0.8§C (max)
LM60B/LM60C 2.7V, SOT-23 Temperature Sensor
Connection Diagram
Typical Application
SOT-23
Top View
TL/H/12681– 1
See NS Package Number MA03B
Order Information
Order
Number
SOT-23
Device Supplied As
Marking
LM60BIM3 T6B 250 Units on Tape and Reel
LM60BIM3X T6B 3000 Units on Tape and Reel
LM60CIM3 T6C 250 Units on Tape and Reel
LM60CIM3X T6C 3000 Units on Tape and Reel
FIGURE 1. Full-Range Centigrade Temperature Sensor
(
e(a
V
6.25 mV/§CcT§C)a424 mV
O
Temperature (T) Typical V
a
125§C
a
100§C
a
25§C
0§C
b
25§C
b
40§C
b
40§Ctoa125§C) Operating from a Single Li-Ion
Battery Cell
C
1996 National Semiconductor Corporation RRD-B30M56/Printed in U. S. A.
TL/H/12681
a
1205 mV
a
1049 mV
a
580 mV
a
424 mV
a
268 mV
a
174 mV
TL/H/12681– 2
O
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Absolute Maximum Ratings (Note 1)
a
Supply Voltage
Output Voltage (
a
Output Current 10 mA
a
V
0.6V) tob0.6V
S
12V tob0.2V
Input Current at any pin (Note 2) 5 mA
JMAX
)
b
65§Ctoa150§C
a
125§C
Storage Temperature
Maximum Junction Temperature (T
ESD Susceptibility (Note 3):
Human Body Model 800V
Machine Model 200V
Electrical Characteristics Unless otherwise noted, these specifications apply for
e
I
1 mA. Boldface limits apply for T
LOAD
e
e
T
A
J
Parameter Conditions
Accuracy (Note 8)
Output Voltage at 0§C
Nonlinearity (Note 9)
Sensor Gain
(Average Slope)
Output Impedance 800 800 X (max)
Line Regulation (Note 10)
Quiescent Current
Change of Quiescent
Current
a
a
a
a
3.0V
2.7V
2.7V
2.7V
a
a
V
10V
S
s
s
a
a
V
3.3V
S
s
s
a
a
V
10V
S
s
s
a
a
V
10V
S
s
s
Temperature Coefficient of
Quiescent Current
e
Long Term Stability (Note 11) T
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 kX resistor into each pin. The machine model is a 200 pF capacitor discharged
directly into each pin.
Note 4: See AN-450 ‘‘Surface Mounting Methods and Their Effect on Product Reliability’’ or the section titled ‘‘Surface Mount’’ found in any post 1986 National
Semiconductor Linear Data Book for other methods of soldering surface mount devices.
Note 5: The junction to ambient thermal resistance ( i
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 the output voltage and
voltage, current, and temperature (expressed in
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.
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.
) at any pin exceeds power supplies (V
I
e
e
T
25§C and represent most likely parametric norm.
J
A
ea
T
J
1000 hours
C).
§
125§C, for
MAX
) is specified without a heat sink in still air.
JA
a
Lead Temperature
SOT Package (Note 4):
Vapor Phase (60 seconds)
Infrared (15 seconds)
a
a
215§C
220§C
Operating Ratings (Note 1)
s
Specified Temperature Range: T
LM60C
LM60B
b
40§CsT
b
25§CsT
MIN
Supply Voltage Range (aVS)
Thermal Resistance, iJA(Note 5) 450§C/W
a
ea
V
T
to T
MIN
; all other limits T
MAX
Typical
(Note 6)
a
424 mV
a
6.25
82
LM60B LM60C
Limits Limits
(Note 7) (Note 7)
g
g
g
a
a
g
g
125 125 mA (max)
g
g
e
A
2.0
3.0
0.6
6.06
6.44
0.3
2.3
110 110 mA (max)
5.0
20
S
e
T
25§C.
J
g
3.0
g
4.0
g
0.8
a
6.00 mV/§C (min)
a
6.50 mV/§C (max)
g
0.3 mV/V (max)
g
2.3 mV (max)
g
5.0 mA (max)
g
20 mA (max)
0.2 mA/
g
0.2
k
I
6.25 mV/§C times the device’s case temperature plus 424 mV, at specified conditions of
GND or V
l
a
VS), the current at that pin should be limited to 5 mA.
I
s
T
A
s
a
A
s
a
A
a
2.7V toa10V
3.0 VDCand
Units
(Limit)
C (max)
§
C (max)
§
C (max)
§
C
§
T
MAX
125§C
125§C
C
§
http://www.national.com 2
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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
Figure 2
.
Thermal Response in
Still Air with Heat Sink
Thermal Response
in Stirred Oil Bath
with Heat Sink
Quiescent Current
vs. Temperature
Supply Voltage
vs Supply Current
TL/H/12681– 3
TL/H/12681– 6
TL/H/12681– 9
TL/H/12681– 4
Start-Up Voltage
vs. Temperature
TL/H/12681– 7
Accuracy vs Temperature
TL/H/12681– 10
Start-Up Response
TL/H/12681– 5
Thermal Response in Still
Air without a Heat Sink
TL/H/12681– 8
Noise Voltage
TL/H/12681– 11
TL/H/12681– 12
TL/H/12681– 13
FIGURE 2. Printed Circuit Board Used
TL/H/12681– 14
for Heat Sink to Generate All Curves.
(/2
Square Printed Circuit Board
×
with 2 oz. Copper Foil or Similar.
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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
ture 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
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 (i
rameter 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:
e
T
where I
on the output.
a
T
J
i
A
is the quiescent current and ILis the load current
Q
The table shown in
perature of the LM60 without any loading, and the thermal
resistance for different conditions.
no heat sink** small heat fin*
i
(§C/W) (§C) (§C/W) (§C)
Still air 450 0.17 260 0.1
Moving air 180 0.07
* Heat sink used is (/2×square printed circuit board with 2 oz. foil with part
attached as shown in
** Part soldered to 30 gauge wire.
Figure 2
FIGURE 3. Temperature Rise of LM60 Due to
Self-Heating and Thermal Resistance (i
a
0.1§C of the surface tempera-
a
[
JA
Figure 3
VSIQ)a(aV
summarizes the rise in die tem-
b
S
SOT-23 SOT-23
b
T
T
JA
J
.
i
A
JA
JA
VO)I
) is the pa-
]
L
b
T
T
J
A
)
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
Figure 4.
LM60 has a maximum output impedance of 800X.Inan
extremely noisy environment it may be necessary to add
some filtering to minimize noise pickup. It is recommended
that 0.1 mF be added from
power supply voltage, as shown in
ronment it may be necessary to add a capacitor from the
output to ground. A 1 mF output capacitor with the 800X
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. LM60 No Decoupling Required
FIGURE 5. LM60 with Filter for Noisy Environment
Over the specified temperature range the
a
VSto GND to bypass the
Figure 5
. In a noisy envi-
TL/H/12681– 15
for Capacitive Load
TL/H/12681– 16
http://www.national.com 4
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2.0 Capacitive Loads (Continued)
3.0 Applications Circuits
FIGURE 8. Conserving Power Dissipation with Shutdown
FIGURE 6. Simplified Schematic
FIGURE 7. Centigrade Thermostat
V
T1
V
T2
(4.1V) R2
e
R2aR1llR3
(4.1V) R2
e
R2llR3aR1
TL/H/12681– 17
TL/H/12681– 18
TL/H/12681– 19
http://www.national.com5
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4.0 Recommended Solder Pads for SOT-23 Package
TL/H/12681– 20
http://www.national.com 6
Page 7
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Page 8
Physical Dimensions inches (millimeters) unless otherwise noted
SOT-23 Molded Small Outline Transistor Package (M3)
Order Number LM60BIM3 or LM60CIM3
NS Package Number MA03B
LM60B/LM60C 2.7V, SOT-23 Temperature Sensor
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL
SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or 2. A critical component is any component of a life
systems which, (a) are intended for surgical implant support device or system whose failure to perform can
into the body, or (b) support or sustain life, and whose be reasonably expected to cause the failure of the life
failure to perform, when properly used in accordance support device or system, or to affect its safety or
with instructions for use provided in the labeling, can effectiveness.
be reasonably expected to result in a significant injury
to the user.
National Semiconductor National Semiconductor National Semiconductor National Semiconductor
Corporation Europe Hong Kong Ltd. Japan Ltd.
1111 West Bardin Road Fax:
Arlington, TX 76017 Email: europe.support@nsc.com Ocean Centre, 5 Canton Rd. Fax: 81-043-299-2408
Tel: 1(800) 272-9959 Deutsch Tel:
Fax: 1(800) 737-7018 English Tel:
http://www.national.com
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
Fran3ais Tel:
Italiano Tel:a49 (0) 180-534 16 80 Fax: (852) 2736-9960
a
49 (0) 180-530 85 86 13th Floor, Straight Block, Tel: 81-043-299-2308
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