LM135 LM235-LM335,A PRECISION TEMPERATURE SENSORS DIRECTLY CALIBRATED IN oK 1oC INITIAL ACCURACY OPERATES FROM 450µA TO 5mA LESS THAN 1Ω DYNAMIC IMPEDANCE Z TO92 (Plastic Package D SO8 (Plastic Micropackage) DESCRIPTION The LM135, LM235, LM335 are precision temperature sensors which can be easily calibrated They operate as a 2-terminal Zener and the breakdown voltage is directly proportional to the absolute temperature at 10mV/oK The circuit has a dynamic impedance of less than 1Ω and operates within a range of current from 450µA to 5mA without alteration of its characteristics Calibrated at +25oC, the LM135, LM235, LM335 have a typical error of less than 1oC over a 100oC temperature range Unlike other sensors, the LM135, LM235, LM335 have a linear output ORDER CODES Part number Temperature Range –55 C, +150 C • • –40oC, +125oC • • • • o o o –40 C, +100 C LM335,A SO8 (Top view) V+ NC NC ADJ NC NC NC V 135-02.EPS V- 135-01.EPS October 1997 D LM235 TO92 (Bottom view) V+ Z LM135 o PIN CONNECTIONS ADJ Package LM135-LM235-LM335,A SCHEMATIC DIAGRAM V 50kΩ 49kΩ 49kΩ p F 10kΩ 15.6kΩ 12pF 600Ω 30kΩ AD J 13.8k Ω 2kΩ 1.1kΩ V ABSOLUTE MAXIMUM RATINGS Symbol IR IF Toper Tstg Parameter Current Reverse Forward Operating Free-air Temperature Range - (note 1) Continuous Intermittent Storage Temperature Range Note : Tj ≤ 150 C o 2/11 LM135 LM235 LM335,A 15 10 15 10 15 10 –55 to +150 +150 to +200 –40 to +125 +125 to +150 –40 to +100 +100 to +125 –65 to +150 –65 to +150 –65 to +150 Unit mA o C o C LM135-LM235-LM335,A TEMPERATURE ACCURACY LM135 - LM235 LM335A Parameter Unit Min Typ Max Min Typ Max 2.95 2.98 3.01 2.92 2.98 3.04 V Operating Output Voltage Tcase = +25oC, IR = 1mA o Uncalibrated Temperature Error (IR = 1mA) o Tcase = +25 C Tmin ≤ Tcase ≤ Tmax C Temperature Error with 25oC Calibration Tmin ≤ Tcase ≤ Tmax., IR = 1mA LM135 - LM235 LM335 LM335A o C 0.5 1.5 0.5 1 o Calibrated Error at Extended Temperature Tcase = Tmax (intermittent) Non-linearity (IR = 1mA) LM335 C LM135 - LM235 LM335 LM335A 0.3 o C 0.3 0.3 1.5 1.5 ELECTRICAL CHARACTERISTICS - (note 1) LM135 - LM235 Parameter Max Operating output voltage change with current 450µA ≤ IR ≤ 5mA at constant temperature 2.5 10 Dynamic Impedance (IR = 1mA) 0.5 0.6 Ω Output Voltage Temperature Drift +10 +10 mV/oC 80 10 80 10 s 0.2 0.2 o Time Stability (Tcase = +125 C) Still Air Air 0.5m/s Stirred Oil Min Typ Max 14 Unit Typ Time Constant Min LM335,A mV o C/kh Note : Accuracy measurements are made in a well-stirred oil bath For other conditions, self heating must be considered 3/11 LM135-LM235-LM335,A 4/11 LM135-LM235-LM335,A 5/11 LM135-LM235-LM335,A APPLICATION HINTS Nominally the output is calibrated at 10mV/oK There is an easy method of calibrating the device for higher accuracies (see typical applications) Precautions should be taken to ensure good sensing accuracy As in the case of all temperatures sensors, self heating can decrease accuracy The LM135, LM235, LM335 should operate with a low current, but sufficient to drive the sensor and its calibration circuit to their maximum operating temperature The single point calibration works because the output of the LM135, LM235, LM335 is proportional to the absolute temperature with the extrapolated output of sensor going to 0V at 0oK ( –273.15oC) Errors in output voltage versus temperature are only slope Thus a calibration of the slope at one temperature corrects errors at all temperatures The output of the circuit (calibrated or not) can be T given by the equation : VOT = VOTO x To where T is the unknown temperature and TO is the reference temperature (in oK) If the sensor is used in surroundings where the thermal resistane is constant, the errors due to self heating can be externally calibrated This is possible if the circuit is biased with a temperature stable current Heating will then be proportional to zener voltage and therefore temperature In this way the error due to self heating is proportional to the absolute temperature as scale factor errors TYPICAL APPLICATIONS BASIC TEMPERATURE SENSOR WIDE OPERATING SUPPLY Vi +5 to +40V V LM134, LM234 LM334 R1 Output 10mV/˚K LM135 LM235 LM335 Output 10mV/˚K LM135 LM235 LM335 CALIBRATED SENSOR AVERAGE TEMPERATURE SENSING +15V V 6kΩ R1 Output 10mV/˚K LM135 LM235 LM335 * Calibrate for 2.982V at +25oC 6/11 68Ω 10kΩ* Output 30mV/˚K LM135 LM235 LM335 LM135-LM235-LM335,A ISOLATED TEMPERATURE SENSOR LM135 LM235 LM335 +15V +15V 50kΩ 1N457 0.1µF m=1 3kΩ 2kΩ 01.µF 1kΩ LM311 10kΩ 510Ω LF398 1N4148 10kΩ Output 10mV/˚K 200pF 27kΩ 100kΩ -15V 1000pF 1N4148 -15V SIMPLE TEMPERATURE CONTROLLER +10V to +30V 2kΩ 10kΩ 10kΩ 5kΩ 0.01µF 1N4568 Heater LM311 10kΩ BUV26 4kΩ LM135 LM235 LM335 7/11 LM135-LM235-LM335,A CENTIGRADE THERMOMETER 1kΩ +15V +15V +15V 6kΩ 12kΩ LM308 { Output 10mV/˚C LM135 LM235 LM335 8.5kΩ 10kΩ LM136 2kΩ * 100pF * Adjust for 2.7315V at output of LM308 DIFFERENTIAL TEMPERATURE SENSOR +15V 12kΩ 200kΩ 12kΩ +15V 20kΩ LM308 20kΩ 180kΩ LM135 LM235 LM335 8/11 -15V 100pF 50kΩ Output 100mV/˚C LM135-LM235-LM335,A THERMOCOUPLE COLD JUNCTION COMPENSATION (compensation for grounded thermocouple) +15V 4.7kΩ Thermocouple R3 Seebeck Coefficient J T K S 377Ω 308Ω 293Ω 45.8Ω 52.3µV/oC 42.8µV/oC o 40.8µV/ C 6.4µV/oC 200kΩ 1% R2 10 kΩ 1N4568 Adjustments : compensates for both sensor and resistor tolerances Short 1N4568 Adjust R1 for SEEBECK coefficient times ambient temperature (in degrees K) across R3 Short LM135 and adjust R2 for voltage across R3 corresponding to thermocouple type J 14.32mV K 11.17mV T 11.79mV S 1.768mV R3* 1MΩ 1% R1 10kΩ LM135 LM235 LM335 12kΩ Thermocouple 71.5kΩ 1% -15V * Select R3 for proper thermocouple type SINGLE POWER SUPPLY COLD JUNCTION COMPENSATION +15V 10kΩ 200kΩ Thermocouple LM135 LM235 LM335 R1 10kΩ R3* +15V 200kΩ R3 R4 Seebeck Coefficient J T K S 1.05kΩ 856Ω 816Ω 128Ω 365Ω 315Ω 300Ω 46.3Ω 52.3µV/oC 42.8µV/oC 40.8µV/oC o 6.4µV/ C Adjustments : Adjust R1 for the voltage across R3 equal to the SEEBECK coefficient times ambient temperature in degrees Kelvin Adjust R2 for voltage across R4 corresponding to thermocouple J 14.32mV K 11.17mV T 11.79mV S 1.768mV Output 1N4568 R2 10 kΩ Thermocouple 1MΩ R4* * Select R3 and R4 for proper thermocouple 9/11 LM135-LM235-LM335,A PM-SO8.EPS PACKAGE MECHANICAL DATA PINS - PLASTIC MICROPACKAGE (SO) A a1 a2 a3 b b1 C c1 D E e e3 F L M S 10/11 Min Millimeters Typ 0.1 0.65 0.35 0.19 0.25 Max 1.75 0.25 1.65 0.85 0.48 0.25 0.5 Min Inches Typ 0.026 0.014 0.007 0.010 Max 0.069 0.010 0.065 0.033 0.019 0.010 0.020 0.189 0.228 0.197 0.244 0.004 45o (typ.) 4.8 5.8 5.0 6.2 1.27 3.81 3.8 0.4 0.050 0.150 4.0 1.27 0.6 0.150 0.016 8o (max.) 0.157 0.050 0.024 SO8.TBL Dimensions LM135-LM235-LM335,A PM-TO92.IMG PACKAGE MECHANICAL DATA PINS - PLASTIC PACKAGE TO92 L B O1 C K O2 a Min 3.2 4.45 4.58 12.7 0.407 0.35 Millimeters Typ 1.27 3.7 5.00 5.03 0.5 Max Min 4.2 5.2 5.33 0.126 0.1752 0.1803 0.5 0.016 0.0138 0.508 Inches Typ 0.05 0.1457 0.1969 0.198 0.1654 0.2047 0.2098 0.0197 0.02 Max TO92TBL Dimensions © 1997 SGS-THOMSON Microelectronics – Printed in Italy – All Rights Reserved SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A 11/11 ORDER CODE : Information furnished is believed to be accurate and reliable However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use No license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics Specification mentioned in this publication are subject to change without notice This publication supersedes and replaces all information previously supplied SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics This datasheet has been download from: www.datasheetcatalog.com Datasheets for electronics components ... to +40V V LM1 34, LM2 34 LM3 34 R1 Output 10mV/˚K LM1 35 LM2 35 LM3 35 Output 10mV/˚K LM1 35 LM2 35 LM3 35 CALIBRATED SENSOR AVERAGE TEMPERATURE SENSING +15V V 6kΩ R1 Output 10mV/˚K LM1 35 LM2 35 LM3 35 *... 1N4568 Heater LM3 11 10kΩ BUV26 4kΩ LM1 35 LM2 35 LM3 35 7/11 LM1 35 -LM2 35 -LM3 35,A CENTIGRADE THERMOMETER 1kΩ +15V +15V +15V 6kΩ 12kΩ LM3 08 { Output 10mV/˚C LM1 35 LM2 35 LM3 35 8.5kΩ 10kΩ LM1 36 2kΩ *... 6/11 68Ω 10kΩ* Output 30mV/˚K LM1 35 LM2 35 LM3 35 LM1 35 -LM2 35 -LM3 35,A ISOLATED TEMPERATURE SENSOR LM1 35 LM2 35 LM3 35 +15V +15V 50kΩ 1N457 0.1µF m=1 3kΩ 2kΩ 01.µF 1kΩ LM3 11 10kΩ 510Ω LF398 1N4148