NTC thermistors for temperature measurement Miniature sensors with bendable wires Series/Type: B57861S Date: March 2013 © EPCOS AG 2013. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS' prior express consent is prohibited.
Temperature measurement B57861S Miniature sensors with bendable wires Applications Temperature measurement Features Short response time High measuring accuracy Tight B value tolerances available Epoxy resin encapsulation PTFE-insulated leads of silver-plated nickel wire, AWG 30 (50 mm) PTFE-insulated leads of silver-plated Cu wire (19 x 0.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Electrical specification and ordering codes R25 Ω Component length mm No. of R/T characteristic B25/100 K B value tolerance = 0.3%, resistance tolerance = ±1% 5k 50 8016 3988 ±0.3% 10 k 50 8016 3988 ±0.3% 30 k 50 8018 3964 ±0.3% B value tolerance = 1%, resistance tolerance = ±1% 10 k 350 8016 3988 ±1% B value tolerance = 1.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Reliability data according to AEC Q200, Rev. D Test Standard High temperature exposure (storage) Biased humidity MIL-STD-202, method 108 MIL-STD-202, method 103 Operational life Temperature cycling Terminal strength (leaded) Test conditions Storage at T = +125 °C t = 1000 h T = 85 °C Relative humidity of air 85% t = 1000 h Test voltage max. 0.3 V DC on NTC1) MIL-STD-202, T = +125 °C method 108 t = 1000 h Test voltage max.
Temperature measurement B57861S Miniature sensors with bendable wires S861 R/T characteristics R/T No. T (°C) 1008 2901 B25/100 = 3560 K B25/100 = 3760 K RT/R25 α (%/K) RT/R25 α (%/K) 55.0 50.0 45.0 40.0 35.0 53.104 39.318 29.325 22.03 16.666 6.1 6.0 5.8 5.7 5.5 63.969 46.179 33.738 24.927 18.611 6.7 6.4 6.2 6.0 5.8 30.0 25.0 20.0 15.0 10.0 12.696 9.7251 7.5171 5.8353 4.5686 5.4 5.2 5.1 4.9 4.8 14.033 10.679 8.198 6.3123 4.9014 5.6 5.4 5.3 5.2 5.1 5.0 0.0 5.0 10.0 15.0 3.
Temperature measurement B57861S Miniature sensors with bendable wires R/T No. T (°C) 160.0 165.0 S861 1008 2901 B25/100 = 3560 K RT/R25 α (%/K) 0.02279 2.0 0.020667 2.0 B25/100 = 3760 K RT/R25 α (%/K) 170.0 175.0 180.0 185.0 190.0 0.01878 0.01709 0.015582 0.014227 0.013012 1.9 1.9 1.8 1.8 1.8 195.0 200.0 205.0 210.0 215.0 0.011934 0.010964 0.0101 0.0093191 0.0085949 1.7 1.7 1.7 1.6 1.6 220.0 225.0 230.0 235.0 240.0 0.0079384 0.0073411 0.
Temperature measurement B57861S Miniature sensors with bendable wires S861 R/T characteristics R/T No. T (°C) 8016 8018 55.0 50.0 45.0 40.0 35.0 96.3 67.01 47.17 33.65 24.26 7.4 7.2 6.9 6.7 6.4 30.24 22.1 6.3 6.1 30.0 25.0 20.0 15.0 10.0 17.7 13.04 9.707 7.293 5.533 6.2 6.0 5.8 5.6 5.5 16.32 12.17 9.153 6.945 5.313 5.9 5.8 5.6 5.4 5.2 5.0 0.0 5.0 10.0 15.0 4.232 3.265 2.539 1.99 1.571 5.3 5.1 5.0 4.8 4.7 4.097 3.183 2.491 1.963 1.557 5.1 4.9 4.8 4.7 4.6 20.0 25.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Mounting instructions 1 Soldering 1.1 Leaded NTC thermistors Leaded thermistors comply with the solderability requirements specified by CECC. When soldering, care must be taken that the NTC thermistors are not damaged by excessive heat. The following maximum temperatures, maximum time spans and minimum distances have to be observed: Dip soldering Iron soldering Bath temperature max. 260 °C max.
Temperature measurement B57861S Miniature sensors with bendable wires 1.3.1 S861 Solderability (test to IEC 60068-2-58) Preconditioning: Immersion into flux F-SW 32. Evaluation criterion: Wetting of soldering areas ≥95%. Solder Bath temperature (°C) Dwell time (s) SnPb 60/40 215 ±3 3 ±0.3 SnAg (3.0 ... 4.0), Cu (0.5 ... 0.9) 245 ±3 3 ±0.3 1.3.2 Resistance to soldering heat (test to IEC 60068-2-58) Preconditioning: Immersion into flux F-SW 32.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Wave soldering Temperature characteristic at component terminal with dual wave soldering Solder joint profiles for silver/nickel/tin terminations Please read Cautions and warnings and Important notes at the end of this document.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Reflow soldering Recommended temperature characteristic for reflow soldering following JEDEC J-STD-020D Profile feature Preheat and soak - Temperature min - Temperature max - Time Average ramp-up rate Liquidous temperature Time at liquidous Peak package body temperature Time (tP)3) within 5 °C of specified classification temperature (Tc) Average ramp-down rate Time 25 °C to peak temperature Tsmin Tsmax tsmin to tsmax Tsmax to T
Temperature measurement B57861S Miniature sensors with bendable wires S861 Solder joint profiles for silver/nickel/tin terminations 1.3.3 Recommended geometry of solder pads Recommended maximum dimensions (mm) Case size inch/mm A B C 0402/1005 0.6 0.6 1.7 0603/1608 1.0 1.0 3.0 0805/2012 1.3 1.2 3.4 1206/3216 1.8 1.2 4.5 1.3.4 Notes Iron soldering should be avoided, hot air methods are recommended for repair purposes.
Temperature measurement B57861S Miniature sensors with bendable wires 2 S861 Conductive adhesion An alternative to soldering is the gluing of thermistors with conductive adhesives. The benefit of this method is that it involves no thermal stress. The adhesives used must be chemically inert. 3 Clamp contacting Pressure contacting by means of clamps is particularly suitable for applications involving frequent switching and high turn-on powers.
Temperature measurement B57861S Miniature sensors with bendable wires 5 S861 Sealing and potting When thermistors are sealed, potted or overmolded, there must be no mechanical stress caused by thermal expansion during the production process (curing / overmolding process) and during later operation. The upper category temperature of the thermistor must not be exceeded. Ensure that the materials used (sealing / potting compound and plastic material) are chemically neutral.
Temperature measurement B57861S Miniature sensors with bendable wires 8 S861 Placement and orientation of SMD NTC thermistors on PCB a) Component placement It is recommended that the PC board should be held by means of some adequate supporting pins such as shown left to prevent the SMDs from being damaged or cracked.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Cautions and warnings See "Important notes". Storage Store thermistors only in original packaging. Do not open the package prior to storage. Storage conditions in original packaging: storage temperature 25 °C ... +45 °C, relative humidity ≤75% annual mean, <95% maximum 30 days per annum, dew precipitation is inadmissible. Do not store thermistors where they are exposed to heat or direct sunlight.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Mounting Ensure that no thermo-mechanical stress occurs due to production processes (curing or overmolding processes) when thermistors are sealed, potted or overmolded or during their subsequent operation. The maximum temperature of the thermistor must not be exceeded. Ensure that the materials used (sealing/potting compound and plastic material) are chemically neutral.
Temperature measurement B57861S Miniature sensors with bendable wires S861 Symbols and terms Symbol English German A AWG Area American Wire Gauge Fläche Amerikanische Norm für Drahtquerschnitte B B25/100 B value B value determined by resistance measurement at 25 °C and 100 °C B-Wert B-Wert, ermittelt durch Widerstandsmessungen bei 25 °C und 100 °C Cth Heat capacitance Wärmekapazität I Current Strom N Number (integer) Anzahl (ganzzahliger Wert) P25 Pdiss Pel Pmax Maximum power at 25 °C
Temperature measurement B57861S Miniature sensors with bendable wires S861 Symbol English German α Temperature coefficient Temperaturkoeffizient ∆ Tolerance, change Toleranz, Änderung δth Dissipation factor Wärmeleitwert τc τa Thermal cooling time constant Thermal time constant Thermische Abkühlzeitkonstante Thermische Zeitkonstante Abbreviations / Notes Symbol English German Surface-mounted devices Oberflächenmontierbares Bauelement * To be replaced by a number in ordering Platzhal
Important notes The following applies to all products named in this publication: 1. Some parts of this publication contain statements about the suitability of our products for certain areas of application. These statements are based on our knowledge of typical requirements that are often placed on our products in the areas of application concerned.
