BS EN IEC 60539-2:2019
$142.49
Directly heated negative temperature coefficient thermistors – Sectional specification. Surface mount negative temperature coefficient thermistors
| Published By | Publication Date | Number of Pages |
| BSI | 2019 | 28 |
IEC 60539-2:2019 is available as IEC 60539-2:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60539-2:2019 is applicable to surface mount directly heated negative temperature coefficient thermistors, typically made from transition metal oxide materials with semiconducting properties. These thermistors have metallized connecting pads or soldering strips and are intended to be mounted directly on to substrates for hybrid circuits or on to printed boards. This edition includes the following significant technical changes with respect to the previous edition:a) revision for the structure in accordance with ISO/IEC Directives, Part 2:2016 (seventh edition) to the extent practicable, and for harmonizing with IEC 60539-1:2016;b) the upper category temperatures of 175 °C, 200 °C, 250 °C, 315 °C, 400 °C in Table 1 have been added; c) the dimensions of 0402M in Annex A have been added.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 2 | National foreword |
| 5 | Annex ZA(normative)Normative references to international publicationswith their corresponding European publications |
| 7 | English CONTENTS |
| 9 | FOREWORD |
| 11 | 1 Scope 2 Normative references 3 Terms and definitions |
| 12 | 4 Information to be given in a detail specification 4.1 General 4.2 Outline drawing and dimensions 4.3 Mounting 4.4 Ratings and characteristics 4.4.1 Particular characteristics 4.4.2 Marking 5 Preferred ratings and characteristics 5.1 Tolerances on rated zero-power resistance |
| 13 | 5.2 Climatic categories 6 Quality assessment procedures 7 Test and measurement procedures 7.1 Mounting 7.2 Drying and recovery 7.2.1 Drying 7.2.2 Recovery 7.3 Visual examination and check of dimensions 7.3.1 Visual examination Tables Table 1 – Upper and lower category temperatures and duration of the damp heat test |
| 14 | 7.3.2 Requirements Figures Figure 1 – Fault: fissure or defect Figure 2 – Fault: crack Figure 3 – Separation or delamination |
| 15 | 7.3.3 Marking Figure 4 – Exposed electrodes Figure 5 – Principal faces |
| 16 | 7.3.4 Dimensions 7.4 Electrical tests 7.4.1 Zero-power resistance 7.4.2 B-value or resistance ratio 7.4.3 Resistance/temperature characteristic Figure 6 – Principal terminations – Gull wing Figure 7 – Principal terminations – Round termination |
| 17 | 7.5 Thermal tests 7.5.1 Dissipation factor (δ) 7.5.2 Thermal time constant by cooling after self-heating (τc) 7.6 Resistance to soldering heat 7.6.1 General 7.6.2 Initial measurement 7.6.3 Test conditions 7.6.4 Recovery 7.6.5 Final inspection, measurements and requirements |
| 18 | 7.7 Solderability 7.7.1 General 7.7.2 Test conditions 7.7.3 Recovery 7.7.4 Final inspection, measurements and requirements 7.8 Rapid change of temperature 7.9 Thermal shock |
| 19 | 7.10 Damp heat, steady state 7.11 Endurance 7.11.1 Endurance at T3 and Pmax |
| 20 | 7.11.2 Endurance at upper category temperature 7.12 Shear (adhesion) test 7.13 Substrate bending test 7.14 Component solvent resistance 7.15 Solvent resistance of marking |
| 21 | Annex A (normative) Guide for the specification and coding of dimensions of surface mount negative temperature coefficient thermistors Figure A.1 – Dimensioning of surface mount thermistors Table A.1 – Dimensions |
| 22 | Annex B (normative) Quality assessment procedure B.1 Primary stage of manufacture B.2 Structurally similar components B.3 Qualification approval procedures B.4 Quality conformance inspection B.4.1 General B.4.2 Qualification approval on the basis of the fixed sample size procedure |
| 24 | B.5 Quality conformance inspection B.5.1 Formation of inspection lots Table B.1 – Fixed sample size test schedule for qualification approval of surface mount negative temperature coefficient thermistors Assessment level EZ |
| 25 | B.5.2 Test schedule B.5.3 Delayed delivery B.5.4 Assessment level Table B.2 – Lot-by-lot inspection |
| 26 | Table B.3 – Periodic test |
