B57550G1202H000

NTC thermistors for temperature measurement Glass-encapsulated sensors, standard type Series/Type: B57550G1 Date: January 2018 © EPCOS AG 2018. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS' prior express consent is prohibited. EPCOS AG is a TDK Group Company. Temperature measurement B57550G1 Glass-encapsulated sensors G1550 Applications Temperature measurement Dimensional drawing Features Glass-encapsulated, heat-resistive and highly stable For temperature measurement up to 300 °C Very short response time Small dimensions Leads: dumet wires (copper-clad FeNi) Options Leads: nickel-plated dumet wires Alternative dimensions available on request Dimensions in mm Approx. weight 40 mg Delivery mode Bulk General technical data Climatic category Max. power Resistance tolerance Rated temperature Dissipation factor Thermal cooling time constant Heat capacity Please read Cautions and warnings and Important notes at the end of this document. (IEC 60068-1) (at 25 °C) (in air) (in air) P25 ∆RR/RR TR δth τc Cth Page 2 of 26 55/300/56 32 ±2, ±3 25 approx. 0.75 approx. 6 approx. 4.5 mW % °C mW/K s mJ/K Temperature measurement B57550G1 Glass-encapsulated sensors G1550 Electrical specification and ordering codes R25 Ω 2k 2.5 k 5k 10 k 10 k 20 k 30 k 50 k 100 k 230 k No. of R/T characteristic 8320 7006 8326 8307 7003 8332 8344 8344 8304 8350 B25/85 K 3406 3546 3483 3478 3612 3993 3992 3992 4072 4240 B0/100 K 3379 3517 3456 3450 3586 3965 3965 3965 4036 4198 B25/100 K 3420 ±1% 3560 ±1% 3497 ±1% 3492 ±1% 3625 ±1% 4006 ±1% 4006 ±1% 4006 ±1% 4092 ±1% 4264 ±1% Ordering code B57550G1202+000 B57550G1252+000 B57550G1502+000 B57550G1103+000 B57550G1103+005 B57550G1203+000 B57550G1303+000 B57550G1503+000 B57550G1104+000 B57550G1234+000 + = Resistance tolerance G = ±2% H = ±3% Note For ordering code B57550G1202+000 and B57550G1252+000 the R/T curve is defined for short wire length (5 mm). In dependence of the real wire length of the glass-encapsulated sensor the wire resistance can be considered for temperatures higher than 100 °C additionally with following equation: Please read Cautions and warnings and Important notes at the end of this document. Page 3 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors G1550 Reliability data Test Standard Storage in dry heat IEC 60068-2-2 Storage in damp heat, steady state Rapid temperature cycling Test conditions Storage at upper category temperature T: 300 °C t: 1000 h IEC Temperature of air: 85 °C 60068-2-67 Relative humidity of air: 85% Duration: 1000 h IEC Lower test temperature: 55 °C 60068-2-14 Upper test temperature: 200 °C Number of cycles: 1000 Please read Cautions and warnings and Important notes at the end of this document. Page 4 of 26 ∆R25/R25 (typical) < 3% Remarks < 2% No visible damage < 2% No visible damage No visible damage Temperature measurement B57550G1 Glass-encapsulated sensors G1550 Reliability data according to AEC-Q200, Rev. D Test Standard High temperature exposure (storage) Operational life MIL-STD-202, method 108 MIL-STD-202, method 108 Temperature cycling Terminal strength (leaded) Test conditions Storage at T = +125 °C t = 1000 h 1000 h / +125 °C Test voltage max. 0.3 V DC on NTC1) JESD 22, Lower test temperature: 55 °C method JA-104 Upper test temperature: 125 °C 1000 cycles Dwell time: max. 30 min at each temperature Transition time in air: max. 1 min MIL-STD-202, Test leaded device integrity method 211 Condition A: 2.27 N2) Mechanical shock MIL-STD-202, method 213, condition C Vibration MIL-STD-202, method 204 Acceleration: 40 g 2) Pulse duration: 6 ms Number of bumps: 3, each direction Acceleration: 5 g t = 20 min 12 cycles in each of 3 directions Frequency range: 10 ... 2000 Hz ∆R25/R25 (typical) < 2% < 2% Remarks No visible damage No visible damage < 2% No visible damage < 1% No visible damage < 1% No visible damage < 1% No visible damage 1) Self heating of the NTC thermistor must not exceed 0.2 K, steady state. Test conditions deviating from AEC-Q200, Rev. D. 2) Deviating from AEC-Q200, Rev. D. Note Contact of NTC thermistors with any liquids and solvents shall be prevented. It must be ensured that no water enters the NTC thermistors (e.g. through plug terminals). Avoid dewing and condensation unless thermistor is specified for these conditions. Please read Cautions and warnings and Important notes at the end of this document. Page 5 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors G1550 R/T characteristics R/T No. T (°C) 7003 7006 8304 B25/100 = 3625 K B25/100 = 3560 K B25/100 = 4092 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 55.0 50.0 45.0 40.0 35.0 63.225 45.46 33.07 24.324 18.081 6.7 6.5 6.3 6.0 5.8 55.947 40.765 30.014 22.321 16.760 6.4 6.2 6.0 5.8 5.6 30.0 25.0 20.0 15.0 10.0 13.575 10.29 7.8716 6.0739 4.7258 5.6 5.4 5.3 5.1 4.9 12.700 9.7089 7.4853 5.8179 4.5572 5.5 5.3 5.1 5.0 4.8 18.275 13.443 9.9853 7.4867 5.6636 6.2 6.0 5.9 5.7 5.5 5.0 0.0 5.0 10.0 15.0 3.7062 2.9287 2.3311 1.8684 1.5075 4.8 4.6 4.5 4.4 4.2 3.5965 2.8586 2.2878 1.8431 1.4943 4.7 4.5 4.4 4.3 4.1 4.3212 3.324 2.5769 2.0127 1.5834 5.3 5.2 5.0 4.9 4.7 20.0 25.0 30.0 35.0 40.0 1.224 1.0000 0.82176 0.67909 0.56422 4.1 4.0 3.9 3.8 3.7 1.2188 1.0000 0.82508 0.68444 0.57073 4.0 3.9 3.8 3.7 3.6 1.2542 1.0000 0.80239 0.64776 0.52598 4.6 4.5 4.3 4.2 4.1 45.0 50.0 55.0 60.0 65.0 0.47122 0.3955 0.33355 0.2826 0.24049 3.6 3.5 3.4 3.3 3.2 0.47829 0.40276 0.34072 0.28953 0.24709 3.5 3.4 3.3 3.2 3.1 0.4295 0.35262 0.291 0.24136 0.20114 4.0 3.9 3.8 3.7 3.6 70.0 75.0 80.0 85.0 90.0 0.20553 0.17637 0.15195 0.13141 0.11406 3.1 3.0 2.9 2.9 2.8 0.21174 0.18217 0.15734 0.13639 0.11866 3.0 3.0 2.9 2.8 2.8 0.16841 0.14164 0.11963 0.10147 0.086407 3.5 3.4 3.3 3.3 3.2 95.0 100.0 105.0 110.0 115.0 0.099352 0.086837 0.076149 0.066989 0.059112 2.7 2.7 2.6 2.5 2.5 0.10358 0.090727 0.079722 0.070269 0.062124 2.7 2.6 2.6 2.5 2.4 0.073867 0.063383 0.054584 0.04717 0.040901 3.1 3.0 3.0 2.9 2.8 120.0 125.0 130.0 135.0 140.0 0.052316 0.046433 0.041327 0.03688 0.032998 2.4 2.4 2.3 2.3 2.2 0.055081 0.048974 0.043662 0.039029 0.034975 2.4 2.3 2.3 2.2 2.2 0.035581 0.03105 0.027179 0.023861 0.021008 2.8 2.7 2.6 2.6 2.5 145.0 150.0 155.0 0.029598 0.026612 0.023984 2.2 2.1 2.1 0.031420 0.028293 0.025536 2.1 2.1 2.0 0.018548 0.016419 0.014573 2.5 2.4 2.4 Please read Cautions and warnings and Important notes at the end of this document. Page 6 of 26 100.11 69.56 48.945 34.853 25.102 7.4 7.2 6.9 6.7 6.5 Temperature measurement B57550G1 Glass-encapsulated sensors R/T No. T (°C) 160.0 165.0 7003 G1550 7006 8304 B25/100 = 3625 K B25/100 = 3560 K B25/100 = 4092 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 0.021665 2.0 0.023099 2.0 0.012967 2.3 0.019613 2.0 0.020939 1.9 0.011566 2.3 170.0 175.0 180.0 185.0 190.0 0.017793 0.016176 0.014735 0.013448 0.012297 1.9 1.9 1.8 1.8 1.8 0.019022 0.017315 0.015774 0.014407 0.013189 1.9 1.9 1.8 1.8 1.7 0.010341 0.0092664 0.0083224 0.0074907 0.0067564 2.2 2.2 2.1 2.1 2.0 195.0 200.0 205.0 210.0 215.0 0.011265 0.010338 0.009504 0.0087516 0.0080718 1.7 1.7 1.7 1.6 1.6 0.012099 0.011120 0.010236 0.0094369 0.0087121 1.7 1.7 1.6 1.6 1.6 0.0061064 0.0055299 0.0050175 0.0045611 0.0041537 2.0 2.0 1.9 1.9 1.9 220.0 225.0 230.0 235.0 240.0 0.0074567 0.0068989 0.0063925 0.0059318 0.005512 1.6 1.5 1.5 1.5 1.5 0.0080536 0.0074542 0.0069079 0.0064094 0.0059539 1.6 1.5 1.5 1.5 1.5 0.0037895 0.0034631 0.0031701 0.0029067 0.0026693 1.8 1.8 1.8 1.7 1.7 245.0 250.0 255.0 260.0 265.0 0.005129 0.004779 0.0044586 0.004165 0.0038955 1.4 1.4 1.4 1.4 1.3 0.0055376 0.0051566 0.0048079 0.0044885 0.0041957 1.4 1.4 1.4 1.4 1.3 0.0024551 0.0022615 0.0020862 0.0019273 0.0017829 1.7 1.6 1.6 1.6 1.5 270.0 275.0 280.0 285.0 290.0 0.0036478 0.0034199 0.0032098 0.003016 0.002837 1.3 1.3 1.3 1.2 1.2 0.0039274 0.0036812 0.0034554 0.0032481 0.0030579 1.3 1.3 1.3 1.2 1.2 0.0016516 0.0015319 0.0014228 0.0013231 0.0012319 1.5 1.5 1.5 1.4 1.4 295.0 300.0 0.0026714 0.002518 1.2 1.2 0.0028831 0.0027226 1.2 1.1 0.0011483 0.0010716 1.4 1.4 Please read Cautions and warnings and Important notes at the end of this document. Page 7 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors G1550 R/T characteristics R/T No. T (°C) 8307 8320 8326 B25/100 = 3492 K B25/100 = 3420 K B25/100 = 3497 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 55.0 50.0 45.0 40.0 35.0 52.624 38.452 28.401 21.194 15.972 6.4 6.2 6.0 5.8 5.6 48.459 35.668 26.524 19.920 15.103 6.2 6 5.8 5.6 5.4 53.680 39.112 28.817 21.459 16.142 6.4 6.2 6.0 5.8 5.6 30.0 25.0 20.0 15.0 10.0 12.149 9.3246 7.2181 5.6332 4.4308 5.4 5.2 5.0 4.9 4.7 11.554 8.9165 6.9383 5.4421 4.3012 5.3 5.1 4.9 4.8 4.6 12.259 9.3959 7.2644 5.6633 4.4503 5.4 5.2 5.1 4.9 4.7 5.0 0.0 5.0 10.0 15.0 3.5112 2.8024 2.252 1.8216 1.4827 4.6 4.4 4.3 4.2 4.1 3.4243 2.7454 2.2158 1.7999 1.4711 4.5 4.4 4.2 4.1 4 3.5236 2.8102 2.2567 1.8243 1.4841 4.6 4.5 4.3 4.2 4.1 20.0 25.0 30.0 35.0 40.0 1.2142 1.0000 0.82818 0.68954 0.57703 3.9 3.8 3.7 3.6 3.5 1.2095 1.0000 0.83132 0.69471 0.58346 3.9 3.7 3.6 3.5 3.4 1.2147 1.0000 0.82785 0.68900 0.57639 3.9 3.8 3.7 3.6 3.5 45.0 50.0 55.0 60.0 65.0 0.48525 0.41 0.34798 0.29663 0.25392 3.4 3.3 3.2 3.2 3.1 0.49239 0.41746 0.35551 0.30405 0.26111 3.3 3.3 3.2 3.1 3 0.48457 0.40931 0.34731 0.29599 0.25332 3.4 3.3 3.2 3.2 3.1 70.0 75.0 80.0 85.0 90.0 0.21824 0.1883 0.16307 0.14174 0.12362 3.0 2.9 2.8 2.8 2.7 0.22512 0.19484 0.16925 0.14754 0.12905 2.9 2.9 2.8 2.7 2.6 0.21768 0.18779 0.16261 0.14131 0.12324 3.0 2.9 2.8 2.8 2.7 95.0 100.0 105.0 110.0 115.0 0.10818 0.094973 0.08364 0.073881 0.06545 2.6 2.6 2.5 2.5 2.4 0.11325 0.099707 0.088049 0.077984 0.069267 2.6 2.5 2.5 2.4 2.3 0.10783 0.094663 0.083361 0.073638 0.065240 2.6 2.6 2.5 2.5 2.4 120.0 125.0 130.0 135.0 140.0 0.058144 0.051794 0.046259 0.04142 0.037179 2.3 2.3 2.2 2.2 2.1 0.061694 0.055095 0.049329 0.044277 0.039838 2.3 2.2 2.2 2.1 2.1 0.057964 0.051640 0.046128 0.041309 0.037085 2.3 2.3 2.2 2.2 2.1 145.0 150.0 155.0 0.033451 0.030166 0.027264 2.1 2.0 2.0 0.035927 0.032474 0.029417 2 2 2 0.033373 0.030102 0.027213 2.1 2.0 2.0 Please read Cautions and warnings and Important notes at the end of this document. Page 8 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors R/T No. T (°C) 160.0 165.0 8307 G1550 8320 8326 B25/100 = 3492 K B25/100 = 3420 K B25/100 = 3497 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 0.024694 2.0 0.026703 1.9 0.024654 2.0 0.022414 1.9 0.024290 1.9 0.022384 1.9 170.0 175.0 180.0 185.0 190.0 0.020385 0.018577 0.016961 0.015514 0.014216 1.9 1.8 1.8 1.8 1.7 0.022139 0.020217 0.018497 0.016953 0.015566 1.8 1.8 1.8 1.7 1.7 0.020364 0.018564 0.016955 0.015515 0.014223 1.9 1.8 1.8 1.8 1.7 195.0 200.0 205.0 210.0 215.0 0.013049 0.011999 0.011051 0.010194 0.0094181 1.7 1.7 1.6 1.6 1.6 0.014317 0.013189 0.012159 0.011231 0.010391 1.7 1.6 1.6 1.6 1.5 0.013063 0.012017 0.011074 0.010222 0.0094500 1.7 1.7 1.6 1.6 1.6 220.0 225.0 230.0 235.0 240.0 0.0087144 0.0080751 0.0074933 0.0069631 0.0064791 1.5 1.5 1.5 1.5 1.4 0.0096285 0.0089347 0.0083021 0.0077243 0.0071956 1.5 1.5 1.5 1.4 1.4 0.0087502 0.0081144 0.0075359 0.0070087 0.0065276 1.5 1.5 1.5 1.4 1.4 245.0 250.0 255.0 260.0 265.0 0.0060366 0.0056316 0.0052602 0.0049193 0.0046059 1.4 1.4 1.4 1.3 1.3 0.0067110 0.0062662 0.0058573 0.0054811 0.0051346 1.4 1.4 1.3 1.3 1.3 0.0060877 0.0056850 0.0053159 0.0049770 0.0046654 1.4 1.4 1.3 1.3 1.3 270.0 275.0 280.0 285.0 290.0 0.0043173 0.0040514 0.003806 0.0035793 0.0033696 1.3 1.3 1.2 1.2 1.2 0.0048149 0.0045199 0.0042472 0.0039950 0.0037616 1.3 1.3 1.2 1.2 1.2 0.0043786 0.0041143 0.0038703 0.0036449 0.0034363 1.3 1.2 1.2 1.2 1.2 295.0 300.0 0.0031753 0.0029952 1.2 1.2 0.0035453 0.0033448 1.2 1.2 0.0032431 0.0030640 1.1 1.1 Please read Cautions and warnings and Important notes at the end of this document. Page 9 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors G1550 R/T characteristics R/T No. T (°C) 8332 8344 8350 B25/100 = 4006 K B25/100 = 4006 K B25/100 = 4264 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 55.0 50.0 45.0 40.0 35.0 97.675 67.930 47.838 34.093 24.576 7.4 7.1 6.9 6.7 6.4 99.651 69.067 48.490 34.465 24.786 7.5 7.2 6.9 6.7 6.5 30.0 25.0 20.0 15.0 10.0 17.909 13.186 9.8062 7.3621 5.5776 6.2 6 5.8 5.6 5.5 18.026 13.251 9.8411 7.3803 5.5866 6.3 6.1 5.9 5.7 5.5 20.096 14.661 10.798 8.0269 6.0195 6.4 6.2 6 5.8 5.7 5.0 0.0 5.0 10.0 15.0 4.2625 3.2848 2.5517 1.9974 1.5750 5.3 5.1 5 4.8 4.7 4.2667 3.2865 2.5522 1.9974 1.5749 5.3 5.1 5 4.8 4.7 4.5526 3.4713 2.6676 2.0654 1.6108 5.5 5.3 5.2 5 4.9 20.0 25.0 30.0 35.0 40.0 1.2508 1.0000 0.80472 0.65163 0.53084 4.5 4.4 4.3 4.2 4 1.2507 1.0000 0.80481 0.65179 0.53105 4.5 4.4 4.3 4.2 4 1.2649 1.0000 0.79564 0.63697 0.51297 4.8 4.6 4.5 4.4 4.3 45.0 50.0 55.0 60.0 65.0 0.43494 0.35834 0.29681 0.24711 0.20676 3.9 3.8 3.7 3.6 3.5 0.43517 0.35858 0.29705 0.24733 0.20695 3.9 3.8 3.7 3.6 3.5 0.41548 0.33837 0.27704 0.22798 0.18854 4.2 4.1 3.9 3.8 3.8 70.0 75.0 80.0 85.0 90.0 0.17381 0.14679 0.12451 0.10607 0.090731 3.4 3.3 3.2 3.2 3.1 0.17398 0.14693 0.12462 0.10615 0.090781 3.4 3.3 3.3 3.2 3.1 0.15666 0.13077 0.10964 0.092312 0.078045 3.7 3.6 3.5 3.4 3.3 95.0 100.0 105.0 110.0 115.0 0.077916 0.067168 0.058116 0.050462 0.043967 3 2.9 2.9 2.8 2.7 0.077940 0.067168 0.058094 0.050422 0.043911 3 2.9 2.9 2.8 2.7 0.066245 0.056445 0.048274 0.041434 0.035686 3.2 3.2 3.1 3 3 120.0 125.0 130.0 135.0 140.0 0.038435 0.033707 0.029651 0.026162 0.023151 2.7 2.6 2.5 2.5 2.4 0.038365 0.033625 0.029589 0.026110 0.023099 2.7 2.6 2.5 2.5 2.4 0.030839 0.026737 0.023253 0.020285 0.017747 2.9 2.8 2.8 2.7 2.6 145.0 150.0 155.0 0.020543 0.018279 0.016307 2.4 2.3 2.3 0.020487 0.018215 0.016235 2.4 2.3 2.3 0.015571 0.013700 0.012086 2.6 2.5 2.5 Please read Cautions and warnings and Important notes at the end of this document. Page 10 of 26 113.81 78.679 55.027 38.917 27.821 7.5 7.3 7 6.8 6.6 Temperature measurement B57550G1 Glass-encapsulated sensors R/T No. T (°C) 160.0 165.0 8332 G1550 8344 8350 B25/100 = 4006 K B25/100 = 4006 K B25/100 = 4264 K RT/R25 α (%/K) RT/R25 α (%/K) RT/R25 α (%/K) 0.014585 2.2 0.014504 2.2 0.010690 2.4 0.013077 2.2 0.012989 2.2 0.0094790 2.4 170.0 175.0 180.0 185.0 190.0 0.011753 0.010588 0.0095600 0.0086500 0.0078436 2.1 2.1 2 2 1.9 0.011659 0.010488 0.0094560 0.0085436 0.0077352 2.1 2.1 2 2 2 0.0084257 0.0075072 0.0067043 0.0060006 0.0053824 2.3 2.3 2.2 2.2 2.2 195.0 200.0 205.0 210.0 215.0 0.0071269 0.0064887 0.0059191 0.0054097 0.0049532 1.9 1.9 1.8 1.8 1.7 0.0070175 0.0063789 0.0058096 0.0053008 0.0048453 1.9 1.9 1.9 1.8 1.8 0.0048381 0.0043578 0.0039330 0.0035564 0.0032220 2.1 2.1 2 2 2 220.0 225.0 230.0 235.0 240.0 0.0045432 0.0041744 0.0038420 0.0035419 0.0032704 1.7 1.7 1.6 1.6 1.6 0.0044367 0.0040694 0.0037386 0.0034402 0.0031706 1.7 1.7 1.7 1.6 1.6 0.0029244 0.0026590 0.0024219 0.0022096 0.0020193 1.9 1.9 1.9 1.8 1.8 245.0 250.0 255.0 260.0 265.0 0.0030243 0.0028010 0.0025980 0.0024131 0.0022445 1.5 1.5 1.5 1.5 1.4 0.0029264 0.0027049 0.0025038 0.0023207 0.0021539 1.6 1.6 1.5 1.5 1.5 0.0018483 0.0016944 0.0015557 0.0014305 0.0013173 1.8 1.7 1.7 1.7 1.6 270.0 275.0 280.0 285.0 290.0 0.0020905 0.0019496 0.0018205 0.0017021 0.0015934 1.4 1.4 1.4 1.3 1.3 0.0020016 0.0018624 0.0017350 0.0016182 0.0015109 1.5 1.4 1.4 1.4 1.4 0.0012147 0.0011216 0.0010371 0.00096018 0.00089010 1.6 1.6 1.6 1.5 1.5 295.0 300.0 0.0014933 0.0014012 1.3 1.3 0.0014124 0.0013216 1.3 1.3 0.00082616 1.5 0.00076774 1.5 Please read Cautions and warnings and Important notes at the end of this document. Page 11 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors G1550 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. 360 °C Soldering time max. 4 s max. 2 s Distance from thermistor min. 6 mm min. 6 mm Under more severe soldering conditions the resistance may change. 1.1.1 Wave soldering Temperature characteristic at component terminal with dual wave soldering 1.2 Leadless NTC thermistors In case of NTC thermistors without leads, soldering is restricted to devices which are provided with a solderable metallization. The temperature shock caused by the application of hot solder may produce fine cracks in the ceramic, resulting in changes in resistance. To prevent leaching of the metallization, solder with silver additives or with a low tin content Please read Cautions and warnings and Important notes at the end of this document. Page 12 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors G1550 should be used. In addition, soldering methods should be employed which permit short soldering times. 1.3 SMD NTC thermistors SMD NTC thermistors can be provided with a nickel barrier termination or on special request with silver-palladium termination. The use of no-clean solder products is recommended. In any case mild, non-activated fluxes should be used. Flux residues after soldering should be minimized. SMD NTCs with AgPd termination are not approved for lead-free soldering. Nickel barrier termination Figure 1 SMD NTC thermistors, structure of nickel barrier termination The nickel barrier layer of the silver/nickel/tin termination (see figure 1) prevents leaching of the silver base metallization layer. This allows great flexibility in the selection of soldering parameters. The tin prevents the nickel layer from oxidizing and thus ensures better wetting by the solder. The nickel barrier termination is tested for all commonly-used soldering methods according to IEC 60068-2-58. Insufficient preheating may cause ceramic cracks. Rapid cooling by dipping in solvent is not recommended. The following test and process conditions apply for nickel barrier termination. Please read Cautions and warnings and Important notes at the end of this document. Page 13 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors 1.3.1 G1550 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. Evaluation criterion: Leaching of side edges ≤1/3. Solder Bath temperature (°C) Dwell time (s) SnPb 60/40 260 ±5 10 ±1 SnAg (3.0 ... 4.0), Cu (0.5 ... 0.9) 260 ±5 10 ±1 1.3.3 Reflow soldering Temperature ranges for reflow soldering acc. to IEC 60068-2-58 recommendations. Please read Cautions and warnings and Important notes at the end of this document. Page 14 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors Profile feature Preheat and soak - Temperature min - Temperature max - Time G1550 Sn-Pb eutectic assembly Pb-free assembly Tsmin Tsmax tsmin to tsmax 100 °C 150 °C 60 ... 120 s 150 °C 200 °C 60 ... 120 s Average ramp-up rate Tsmax to Tp 3 °C/ s max. 3 °C/ s max. Liquidous temperature Time at liquidous TL tL 183 °C 40 ... 150 s 217 °C 40 ... 150 s Peak package body temperature Tp 215 °C ... 260 °C1) 235 °C ... 260 °C Time above (TP 5 °C) tp 10 ... 40 s 10 ... 40 s Average ramp-down rate Tp to Tsmax 6 °C/ s max. 6 °C/ s max. max. 8 minutes max. 8 minutes Time 25 °C to peak temperature 1) Depending on package thickness. Notes: All temperatures refer to topside of the package, measured on the package body surface. Number of reflow cycles: 3 Iron soldering should be avoided, hot air methods are recommended for repair purposes. Solder joint profiles for silver/nickel/tin terminations Please read Cautions and warnings and Important notes at the end of this document. Page 15 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors 1.3.4 G1550 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 2 Conductive adhesion An alternative to soldering for silver-palladium terminated components 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. 4 Robustness of terminations (leaded types) The leads meet the requirements of IEC 60068-2-21. They may not be bent closer than 4 mm from the solder joint on the thermistor body or from the point at which they leave the feedthroughs. During bending, any mechanical stress at the outlet of the leads must be removed. The bending radius should be at least 0.75 mm. Please read Cautions and warnings and Important notes at the end of this document. Page 16 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors Tensile strength: G1550 Test Ua1: Value of applied force for Ua1 test: Diameter (d) of Force with tolerance of ±10% corresponding round leads ∅ ≤ 0.25 mm 1.0 N 0.25 < ∅ ≤ 0.35 mm 2.5 N 0.35 < ∅ ≤ 0.50 mm 5.0 N 0.50 < ∅ ≤ 0.80 mm 10.0 N Bending strength: Test Ub: Two 90°-bends in opposite directions Value of applied force for Ub test: Diameter (d) of Force with tolerance of ±10% corresponding round leads ∅ ≤ 0.25 mm 0.5 N 0.25 < ∅ ≤ 0.35 mm 1.25 N 0.35 < ∅ ≤ 0.50 mm 2.5 N 0.50 < ∅ ≤ 0.80 mm 5N Torsional strength: Test Uc: severity 2 The lead is bent by 90° at a distance of 6 to 6.5 mm from the thermistor body. The bending radius of the leads should be approx. 0.75 mm. Two torsions of 180° each (severity 2). When subjecting leads to mechanical stress, the following should be observed: Tensile stress on leads During mounting and operation tensile forces on the leads are to be avoided. Bending of leads Bending of the leads directly on the thermistor body is not permissible. A lead may be bent at a minimum distance of twice the wire's diameter +4 mm from the solder joint on the thermistor body. During bending the wire must be mechanically relieved at its outlet. The bending radius should be at least 0.75 mm. Please read Cautions and warnings and Important notes at the end of this document. Page 17 of 26 Temperature measurement B57550G1 Glass-encapsulated sensors 5 G1550 Sealing and potting Sealing or potting processes can affect the reliability of the component. 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. As thermistors are temperature sensitive components it should be considered that molding can affect the thermal surrounding and may influence e.g. the response time. Extensive testing is encouraged in order to determine whether overmolding or potting influences the functionality and/ or reliability of the component. 6 Cleaning Cleaning processes can affect the reliability of the component. If cleaning is necessary, mild cleaning agents are recommended. Cleaning agents based on water are not allowed. Washing processes may damage the product due to the possible static or cyclic mechanical loads (e.g. ultrasonic cleaning). They may cause cracks which might lead to reduced reliability and/ or lifetime. 7 Storage In order to maintain their solderability, thermistors must be stored in a non-corrosive atmosphere. Humidity, temperature and container materials are critical factors. Do not store SMDs where they are exposed to heat or direct sunlight. Otherwise, the packing material may be deformed or SMDs may stick together, causing problems during mounting. After opening the factory seals, such as polyvinyl-sealed packages, use the SMDs as soon as possible. The components should be left in the original packing. Touching the metallization of unsoldered thermistors may change their soldering properties. Storage temperature: 25 °C up to 45 °C Relative humidity (without condensation): ≤75% annual mean