View FM5008_4583415.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

FM50 -- Analog Temperature Sensor
April 2008
FM50 -- Analog Temperature Sensor
Features
Analog Output: 10mV/C Range: -40 to 125C Range Accuracy: 2C at 25C Supply Current: 170A Maximum Output Drive: 25A Self-heating: <0.1C Operating Voltage: +2.4V to +6V
Description
As a precision CMOS temperature sensor, the FM50 is cost effective for accurate, low-power, temperaturemonitoring applications. Output voltage versus temperature is extremely linear. With no load, the supply current is typically 130A. For normal operation, the load on VOUT should be 100K or less. 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. Accuracy is typically 0.5C at room temperature, and better than 2C from 0 to 75C. FM50 is available in a 3-pin SOT-23 package.
Applications
Mobile Phones Computers Battery Management Office Equipment HVAC Power Supply Modules Disk Drives Automotive
Ordering Information
Part Number
FM50S3X
Operating Temperature Range
-40 to +125C
Package
3-Pin SOT-23
Packing Method
3000 Units, Tape and Reel
All packages are lead free per JEDEC: J-STD-020B standard.
Figure 1. Output Voltage vs. Temperature
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1 www.fairchildsemi.com
FM50 -- Analog Temperature Sensor
Pin Configuration
Figure 2. Pin Configuration
Pin Definitions
Pin #
1 2 3
Name
VDD VOUT GND
Type
Power Analog Output Power
Description
Power Supply. 2.4 to 6.0V. Temperature Sensor. Analog output voltage indicating temperature. VOUT = 500+10T(C) mV. Ground.
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1
www.fairchildsemi.com 2
FM50 -- Analog Temperature Sensor
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only.
Symbol
VDD VOUT IOUT TJ TSTG TL ESD
Parameter
Supply Voltage Output Voltage Output Current Operating Temperature Range Storage Temperature Range Lead Soldering Temperature Human Body Model, JESD22-A114 Machine Model, JESD22-A115
(2) (1)
Min.
Max.
+7 VDD+0.5 10
Unit
V V A C C C V
-50 -60
+150 +150 +220 2000 250
Notes: 1. Human body model: 100pF capacitor discharged through a t 1.5kW resister into each pin. 2. Machine model: 200pF capacitor discharged directly into each pin.
Electrical Characteristics
Limits apply for -40C TA +125C and VDD=+5.0V unless otherwise noted. These specifications are guaranteed only for the test conditions listed.
Symbol
AOUT
Parameter
Sensitivity Output at 25C
Conditions
Min.
9.7 740
Typ.
10.0 750 0.5 1.0 1
Max.
10.3 760 +2.0 +3.5 +3 +125 +0.8 1750
Units
mV/C mV C C C mV A mA A
Transfer Characteristics
TA=+25C Accuracy TA Output VOUT IONSN IONSG IOL ROUT RLOAD Power VDD IQ Package JA Thermal Resistance Supply Voltage Quiescent Current No Output Load Output Voltage Range Output Current Source Output Current Sink Output Resistance Load Regulation 100k Load at 25C Sensing Surge
(3)
-2.0 -3.5 -3 -40 -0.8 100
TA=-40C (TMIN) TA=+125C (TMAX)
Temperature Range Non-Linearity
(4)
25 50 1 10
k mV/mA
2.4
6.0 170 260
V A C/W
Notes: 3. Accuracy (expressed in C)= difference between calculated output voltage and measured output voltage. Calculated output voltage =10m/VC multiplied by the device's case temperature at specific conditions of temperature, voltage and power supply, added to 500mV. 4. Non-linearity is defined as the deviation of the output voltage vs. temperature curve from the best fit straight line over the rated temperature range.
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1 www.fairchildsemi.com 3
FM50 -- Analog Temperature Sensor
Typical Performance Characteristics
Figure 3. Accuracy vs. Temperature
Figure 4. Typical IDD vs. Temperature
Figure 5. Typical Sensitivity to Supply Voltage
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1
www.fairchildsemi.com 4
FM50 -- Analog Temperature Sensor
Functional Description
The FM50 contains a thermal diode, calibration circuits, and amplifiers. Since the FM50 is calibrated at 33C, the nominal output in mV is: VOUT = 830 + 10 * (T-33) where T is the expressed in C. thermal junction (1) temperature
Thermal Delay Errors
For measurement accuracy of the order of tenths of 1C, adequate settling time must be allowed. For a typical circuit board installation, 15 minutes should be allowed to elapse after reading temperature within 1~2C of the expected final value. Once VOUT has ceased to slew and is stable (with or without about 0.1C noise) for about five minutes, temperature can be calculated.
At 33C, the tolerances are: Offset is 3mV. Slope is 0.3mV/C. These values accommodate the specified accuracies at -40, +25, and +125C. Output structure is an N-channel CMOS transistor driving a P-channel load. Available current is typically 50A to ground. Series resistance is typically 7k, charging and 2k, discharging through a capacitor connected from VOUT to ground. Following application of power to VDD, VOUT is accurate after a delay of approximately 80ms.
Location Errors
Position is source of error. Even within a controlled thermal environment, changing location by a few inches can lead to errors of several tenths of 1C.
Mounting
The FM50 can be easily mounted by gluing or cementing it to a surface. In this case, its temperature will be within about 0.2C of the temperature of the surface to which it is attached 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 die will be at an intermediate temperature between the surface temperature and the air temperature. To ensure good thermal conductivity, the backside of the die is directly attached to the GND pin. The lands and traces to the FM50 are part of the printed circuit board, for which the temperature is being measured. These printed circuit board lands and traces do 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 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 it connections.
Application Information
Although the FM50 is a simple device, care must be taken to ensure that temperature is measured accurately. The major sources of errors are: Voltage Errors Thermal Delay Errors Location Errors
Voltage Errors
Figure 6. Recommended Electrical Connections A Kelvin connection is recommended to avoid errors due to voltage drops in the ground connections. Although the typical 130A supply current draw only causes a 130V error; if the series resistance is 1, a 100mA current supply to adjacent circuits can cause a 10mV drop across 100m (10m is a typical value for soldered joints or contact resistance), leading to a 1C error. For this reason, the FM50 should be Kelvin connected, as shown in Figure 6.
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1
www.fairchildsemi.com 5
FM50 -- Analog Temperature Sensor
Typical Application Circuits
Figure 7. Serial Output Temperature to Digital Converter (Full Scale = +125C)
Figure 8. Parallel Output Temperature to Digital Converter (Full Scale = +125C)
Figure 9. Thermostat / Fan Controller
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1 www.fairchildsemi.com 6
FM50 -- Analog Temperature Sensor
Physical Dimensions
Figure 10. 3-Pin SOT Package
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild's worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor's online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1
www.fairchildsemi.com 7
FM50 -- Analog Temperature Sensor
(c) 2004 Fairchild Semiconductor Corporation FM50 * Rev. 1.1.1
www.fairchildsemi.com 8

▲Up To Search▲

Price & Availability of FM5008

	To Download FM5008 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .