FAIRCHILD FM50S3X_NL

www.fairchildsemi.com
FM50
Analog Temperature Sensor
Features
Description
•
•
•
•
•
•
•
As a precision CMOS temperature sensor, the FM50 is
cost-effective for accurate low-power temperature monitoring applications. Output voltage versus temperature is
extremely linear. With no load, the supply current is
typically 130µA. For normal operation, the load on V OUT
should be 100KΩ or less.
Analog output: 10 mV/°C
Range: -40 to 125°C range:
Accuracy: ±2°C at 25°C
Supply Current, 170 µA max.
Output Drive, 25 µA
Self-heating < 0.1°C
Operating Voltage: +2.4V to +6V
In a typical application, a remotely mounted FM50 is
monitored by a microcontroller with an analog A/D
converter input. Alternatively, the FM50 can drive a
comparator with a high impedance input.
Applications
•
•
•
•
•
•
•
•
Mobile Phones
Computers
Battery Management
Office Equipment
HVAC
Power Supply Modules
Disk Drives
Automotive
Accuracy is typically ± 0.5°C at room temperature; and
better than ±2°C from 0 to 75°C.
Available in both standard and Lead Free 3-pin SOT-23
package.
Thermal Response
VOUT (mV)
1750
750
500
100
-50 -40
-25
0
25
50
75
100
125
Temperature ( C)
Temperature ( C) =
VOUT - 500 mV
10 mV/ C
FM50 Output Voltage vs. Temperature
REV. 1.1.0 10/5/04
FM50
PRODUCT SPECIFICATION
Pin Assignments
GND
3
FM50
1
2
VDD
VOUT
Pin Descriptions
Pin Name Pin No.
2
Type
Function
VOUT
2
Analog Output
Temperature Sense. Analog output voltage indicating temperature.
VOUT = 500+10T(°C) mV
VDD
1
Power
Supply Voltage. 2.4 to 6.0V
GND
3
Power
Ground.
REV. 1.1.0 10/5/04
PRODUCT SPECIFICATION
FM50
Absolute Maximum Ratings1
Parameter
Min.
Typ.
Max.
Units
Supply Voltage
+7
V
Output Voltage
VDD + 0.5
V
10
µA
-50
+150
°C
-60
+150
°C
Lead Soldering Temperature
220
°C
ESD2
Human Body Model
Machine Model
2000
250
V
V
Output Current
Operating Temperature
Range2
Storage Temperature Range
Notes:
1. Absolute maximum ratings are limits beyond which operation may cause permanent damage to the device. These are stress
ratings only; functional operation at or above these limits is not implied.
2. Operating ratings are conditions for which the device is intended to be functional without specific guaranteed performance
limits. For guaranteed specifications and test conditions refer to Electrical Characteristics.
3. Human Body Model: 100pF capacitor discharged through a 1.5kOhm resistor into each pin. Machine Model: 200pF capacitor
discharged directly into each pin.
Electrical Characteristics4
Limits apply for -40°C ≤ TA ≤ +125°C and VDD = +5.0V unless otherwise noted.
Parameter
Transfer Characteristic
Sensitivity
Output at 25°C
Accuracy5
Temperature Range
Non-Linearity6
Output
Output Voltage Range
Output Current Source
Output Current Sink
Output resistance
Load regulation
Power
Supply Voltage
Quiescent Current
Package
Thermal Resistance
Symbol
Conditions
Min
Typ
Max
Units
10
750
10.3
760
mV/°C
mV
TA = +25°C
TA = -40°C (TMIN)
TA = +125°C (TMAX)
9.7
740
-2
-3.5
-3
±0.5
±1
±1
+2
+3.5
+3
°C
°C
°C
°C
°C
AOUT
-40
-0.8
+125
+0.8
100
IONSN
IONSG
IOL
Sensing
Surge
50
100kΩ load at 25°C
VDD
IS
1750
25
1
10
2.4
6.0
170
No output load
260
mV
µA
mA
µA
kΩ
mV/mA
V
µA
°C/W
Notes:
4. These specifications are guaranteed only for the test conditions listed.
5. Accuracy (expressed in °C) = Difference between calculated output voltage and measured output voltage. Calculated output
voltage = 10mV/°C multiplied by the device’s case temperature at specified conditions of temperature, voltage and power
supply, added to 500mV.
6. Non-linearity 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.
REV. 1.1.0 10/5/04
3
FM50
PRODUCT SPECIFICATION
Typical Performance Characteristics
4.0
upper spec limit
3.0
VDD = +5V
Accuracy (°C)
2.0
1.0
0.0
-1.0
-2.0
-3.0
lower spec limit
-4.0
0
-50
50
150
100
Temperature (°C)
Figure 1. Accuracy vs. Temperature
VOUT Deviation from 5V Value (mV)
140.0
Supply Current (uA)
120.0
100.0
80.0
60.0
40.0
20.0
0.0
-50
-30
-10
10
30
50
70
90
110
130
Temperature (°C)
Figure 2. Typical IDD versus Temperature
Description
Within the FM50 are a thermal diode, calibration circuits
and amplifiers. Since the FM50 is calibrated at 33°C,
the nominal output in mV is:
V OUT = 830 + 10 • ( T – 33 )
5.0
4.0
3.0
2.0
1.0
0.0
-1.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
VDD Volts
Figure 3. Typical Sensitivity to Supply Voltage
These values accommodate the specified accuracies at -40,
25 and +125°C.
Output structure of the FM50 is an n-channel CMOS transistor driving a p-channel load. Available current is typically 50
µA to ground. Series resistance is typically 7 k Ω, charging
and 2 kΩ, discharging through a capacitor connected from
VOUT to ground.
where T is the thermal junction temperature expressed in °C.
At 33°C, the tolerances are as follows:
1.
Offset is ±3mV
2.
Slope, ±0.3mV/°C
4
Following application of power to VDD, VOUT is accurate
following a delay of approximately 80 msec.
REV. 1.1.0 10/5/04
PRODUCT SPECIFICATION
FM50
Applications Information
Although the FM50 is a simple device, care must be taken to
ensure that temperature is measured accurately. There are
two major sources of errors:
3.
Voltage errors.
4.
Thermal Delay Errors.
5.
Location errors
Location Errors
Position is another source of error. Even within a controlled
thermal environment, changing location by a few inches can
lead to errors of several tenths of 1°C
Mounting
The FM50 can be easily mounted by gluing or cementing it
to a surface. In this case, its temperature will be within about
0.2°C of the temperature of the surface it is attached to if the
ambient air temperature is almost the same as the surface
temperature. If the air temperature is much higher or lower
than the surface temperature, the actual temperature of the
FM50 die will be at an intermediate temperature between the
surface temperature and the air temperature.
Voltage Errors
VDD
FM50
GND(power)
VOUT
GND(sense)
Figure 4. Recommended Electrical Connections
A Kelvin connection is recommended to avoid errors due to
voltage drops in the ground connections. Although the
typical 130µA supply current draw of the FM50 will only
cause a 130µV error if the series resistance is 1 Ω, a 100 mA
current supply to adjacent circuits can cause a 10mV drop
across 100mΩ (10mΩ is a typical value for soldered joints or
contact resistance), leading to a 1°C error. For this reason,
the FM50 should be Kelvin connected as shown in Figure 4.
Thermal Delay Errors
To ensure good thermal conductivity, the backside of the
FM50 die is directly attached to the GND pin. The lands and
traces to the FM50 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 FM50’s temperature to deviate from the
desired temperature.
Alternatively, the FM50 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 FM50 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 paint or dips can be used to ensure
that moisture cannot corrode the FM50 or its connections.
For measurement accuracy of the order of tenths of 1°C,
adequate settling time must be allowed. For a typical circuit
board installation, 15 minutes should be allowed to elapse
following reading of temperature within 1 - 2°C of the
expected final value. Once VOUT has ceased to slew and
is stable (with or without about ±0.1°C noise) for about 5
minutes, temperature can be calculated.
REV. 1.1.0 10/5/04
5
FM50
PRODUCT SPECIFICATION
Typical Applications Circuits
3.9K
VTEMP
IN
REF
1.75V
FM50
U1
Serial
Analog-to-Digital
Converter
SERIAL
DATA OUT
U3
100K
FB
1µF
Adjustable
Shunt Voltage
Reference
CLOCK
U2
10K
ENABLE
Figure 4. Serial Output Temperature to Digital Converter (Full Scale = +125°C)
5V
30K
PARALLEL
DATA
OUTPUT
8
VTEMP
FM50
IN
U1
+
5K
1µF
Parallel Output
Analog-to-Digital
Converter
VREF
U2
1.75V
INTR
U3
CS
RD
15K
WR
Figure 5. Parallel Output Temperature to Digital Converter (Full Scale = +125°C)
6
REV. 1.1.0 10/5/04
PRODUCT SPECIFICATION
FM50
Typical Applications (continued)
V+
R3
R4
R1
VT
4.1V
Shunt
Voltage
Reference
U1
U3
0.1µF
R2
V+
-
FM50
VOUT
+
VTEMP
U2
Figure 6. Thermostat/Fan Controller
REV. 1.1.0 10/5/04
7
FM50
PRODUCT SPECIFICATION
Mechanical Dimensions inches (millimeters) unless otherwise noted
SOT-23 FS Package Code AU
0.110 (2.800)
0.120 (3.040)
0.047 (1.20)
0.055 (1.40)
0.083 (2.100)
0.104 (2.640)
PIN 1
0.035 (0.890)
0.041 (1.030)
0.070 (1.780)
0.081 (2.050)
0.017 (0.450)
0.024 (0.600)
0.035 (0.890)
0.044 (1.120)
0.0005 (0.013)
0.004 (0.100)
SEATING
PLANE
0.015 (0.370)
0.020 (0.510)
0.015 (0.085)
0.007 (0.180)
10°
0°
0.0217 REF (0.55) REF
Ordering Information
Part Number
Package
Temperature Range
Shipping
FM50S3X
3-Pin SOT-23
-40°C to +125°C
Tape and Reel, 3000 units/reel
FM50S3X_NL
3-Pin SOT-23
-40°C to +125°C
Tape and Reel, 3000 units/reel
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO
ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME
ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN;
NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.
LIFE SUPPORT POLICY
FAIRCHILD’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 FAIRCHILD 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 (c) whose failure to
perform when properly used in accordance with
instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of the
user.
2. A critical component in 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.
www.fairchildsemi.com
10/5/04 0.0m 003
Stock#DS30000050
2004 Fairchild Semiconductor Corporation