Issued March 1997 232-2958 Data Pack E Data Sheet Temperature sensor ic LM35CZ and LM35DZ RS stock numbers 317-954 and 317-960 The LM35 is a precision semiconductor temperature sensor giving an output of 10mV per degree Centigrade. Unlike devices with outputs proportional to the absolute temperature (in degrees Kelvin) there is no large offset voltage which, in most applications, will have to be removed. Accuracies of 1/4C at room temperature or 3/4C over the full temperature range are typical. Absolute maximum ratings (Note 10) Supply voltage _____________________+35V to -0.2V Output voltage _______________________+6V to -1.0V Output current ____________________________10mA Storage temperature, TO-92 package _-60C to +150C Lead temperature (soldering, 10 seconds) ____260C Specified operating temperature range TMIN to TMAX (Note 2) LM35CZ ________________________ -40C to +110C LM35DZ __________________________ 0C to +100C Features Output proportional to C Wide temperature range -40C to +110C (CZ version) Accurate 1/4C at room temperature typical Linear output 0.2C typical Low current drain (60A typical) Low self heating (0.08C typical) Output impedance 0.1 at 1mA Standard T092 package. Pin connections Package details 232-2958 Electrical characteristics (Note 1) (Note 6) Parameter Conditions LM35CZ, LM35DZ Tested Design Typical Limit Limit (Note 4) (Note 5) Accuracy, LM35, LM35C (Note 7) TA = +25C TA = -10C TA = TMAX TA = TMIN 0.4 0.5 0.8 0.8 1.0 Accuracy, LM35D (Note 7) TA = +25C TA = TMAX TA = TMIN 0.6 0.9 0.9 1.5 Non linearity (Note 8) TMINTATMAX Sensor gain (Average slope) 1.5 1.5 2.0 Units (Max.) C C C 2.0 2.0 C C C 0.2 0.5 C TMINTATMAX +10.0 +9.8 +10.2 mV/C Load regulation (Note 3) 0IL1mA TA = +25C TMINTATMAX 0.4 0.5 2.0 Line regulation (Note 3) TA = +25C 4VVS30V 0.01 0.02 0.1 Quiescent current (Note 9) VS = +5V, +25C VS = +5V VS = +30V, +25C VS = +30V 56 91 56.2 91.5 80 4VVS30V, +25C 4VVS30V 0.2 0.5 2.0 Change of quiescent current (Note 3) Temperature coefficient of quiescent current 5.0 mV/mA mV/mA 0.2 mV/V mV/V 141 A A A A 3.0 A A +0.39 +0.7 A/C +2.0 C Minimum temperature for rated accuracy In circuit of Figure 1, IL = 0 +1.5 Long term stability TJ-TMAX, for 1000 hours +0.08 138 82 C Notes: 1. Unless otherwise noted, these specifications apply: -40TJ + 110C for the LM35C and 0TJ+100C for the LM35D. VS = +5Vdc and ILOAD = 50A, in the circuit of Figure 2. These specifications also apply from +2C to TMAX in the circuit of Figure 1. Specifications in boldface apply over the full rated temperature range. 2. Thermal resistance of the TO-92 package is 180C/W junction to ambient. 3. 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. 4. Tested limits are guaranteed and 100% tested in production. 5. Design limits are guaranteed (but not 100% production tested) over the indicated temperature and supply voltage ranges. These limits are not used to calculate outgoing quality levels. 6. Specifications in boldface apply over the full rated temperature range. 7. Accuracy is defined as the error between the output voltage and 10mV/C times the device's case temperature, at specified conditions of voltage, current, and temperature (expressed in C). 8. 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. 9. Quiescent current is defined in the circuit of Figure 1. 10. Absolute maximum ratings indicate limits beyond which damage to the device may occur. dc and ac electrical specifications are not ensured when operating the device at absolute maximum ratings. 2 232-2958 Application notes Figure 4 Figure 1 The circuit shown in Figure 1 is a basic single ended temperature sensor capable of measuring between +2C and +100C or +110C depending on version. To measure negative temperatures a negative supply is required as shown in Figure 2. The circuits below show some typical applications of these temperature sensors. Figure 5 Two-wire remote temperature sensor with sensor grounded Figure 2 R1 should be selected as follows: R1 = -Vs 50 3 10 -6 Care must be taken when driving capacitive load, such as long cables or any load exceeding 50pF. To remove the effect of capacitive loads the circuit shown Figure 3 should be used, however the resistor is added to the output impedance making this circuit suitable for connection to high impedance loads only. Figure 4 shows a circuit when will overcome this problem and also give protection from radiated interference from relays or any other source of electrical noise. Figure 6 Two-wire remote temperature sensor Figure 3 3 232-2958 Figure 7 Temperature sensor, single supply, capable of measuring negative temperatures Figure 8 Centigrade thermometer Figure 9 Expanded scale thermometer The information provided in RS technical literature is believed to be accurate and reliable; however, RS Components assumes no responsibility for inaccuracies or omissions, or for the use of this information, and all use of such information shall be entirely at the user's own risk. No responsibility is assumed by RS Components for any infringements of patents or other rights of third parties which may result from its use. Specifications shown in RS Components technical literature are subject to change without notice. RS Components, PO Box 99, Corby, Northants, NN17 9RS An Electrocomponents Company Telephone: 01536 201234 (c) RS Components 1997