IEC 60738-1 pdf download

IEC 60738-1 pdf download Thermistors – Directly heated positive temperature coefficient – Part 1: Generic specification
1 Scope
This part of IEC 60738 describes terms and methods of test for positive step-function temperature coefficient thermistors, insulated and non-insulated types typically made from ferro-electric semi-conductor materials. It establishes standard terms, inspection procedures and methods of test for use in detail specifications for Qualification Approval and for Quality Assessment Systems for electronic components.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60027 (all parts), Letter symbols to be used in electrical technology
IEC 60050 (all parts), International Electrotechnical Vocabulary (IEV)
IEC 60062, Marking codes for resistors and capacitors
IEC 60068-1 :1 988, Environmental testing – Part 1: General and guidance Amendment 1 (1 992)
IEC 60068-2-1 :1 990, Environmental testing – Part 2: Tests – Tests A: Cold Amendment 1 (1 993) Amendment 2 (1 994)
IEC 60068-2-2:1 974, Environmental testing – Part 2: Tests – Tests B: Dry heat Amendment 1 (1 993)
IEC 60068-2-6, Environmental testing – Part 2: Tests – Test Fc: Vibration (sinusoidal)
IEC 60068-2-1 1 , Environmental testing – Part 2: Tests – Test Ka: Salt mist
IEC 60068-2-1 3, Environmental testing – Part 2: Tests – Test M: Low air pressure
IEC 60068-2-1 4:1 984, Environmental testing – Part 2: Tests – Test N: Change of temperature Amendment 1 (1 986)
IEC 60068-2-20:1 979, Environmental testing – Part 2: Tests – Test T: Soldering Amendment 2 (1 987)
IEC 60068-2-21 , Environmental testing – Part 2-21: Tests – Test U: Robustness of terminations and integral mounting devices
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
type
group of components having similar design features and the similarity of whose manufacturing techniques enables them to be grouped together either for qualification approval or for quality conformance inspection
They are generally covered by a single detail specification
NOTE Components described in several detail specifications, may, in some cases, be considered as belonging to the same type but they are generally covered by a single detail specification.
3.2
style
variation within a type having specific nominal dimensions and characteristics
3.3
thermistor
thermally sensitive semiconducting resistor which exhibits a significant change in electrical resistance with a change in body temperature
3.4
positive temperature coefficient thermistor
thermistor, the resistance of which increases with its increasing temperature throughout the useful part of its characteristic
3.5
positive step-function temperature coefficient thermistor
PTC
thermistor which shows a step-like increase in its resistance when the increasing temperature reaches a specific value
A PTC thermistor will show secondary effects which are to be taken into account
3.6
zero-power resistance
R T
value of the resistance of a PTC thermistor, at a given temperature, under conditions such that the change in resistance due to the internal generation of heat is negligible with respect to the total error of measurement