DIN EN 60384-21:2012-09

This part of IEC 60384 is applicable to fixed unencapsulated surface mount multilayer capacitors of ceramic dielectric, Class 1, for use in electronic equipment. These capacitors have metallized connecting pads or soldering strips and are intended to be mounted on printed boards, or directly onto substrates for hybrid circuits. This standard prescribes preferred ratings and characteristics and selects from IEC 60384-1 the appropriate quality assessment procedures, tests and measuring methods and gives general performance requirements for this type of capacitor. Test severities and requirements prescribed in detail specifications referring to this sectional specification should be of equal or higher performance level, lower performance levels are not permitted. Capacitors for electromagnetic interference suppression are not included, but are covered by IEC 60384-14. For the purposes of this document, the terms and definitions given in IEC 60384-1 and the following apply. A surface mount capacitor is a capacitor whose small dimensions and nature or shape of terminations make it suitable for surface mounting in hybrid circuits and on printed boards, a fixed capacitor, ceramic dielectric, class 1 is a capacitor specially designed and suited for resonant circuit application where low losses and high stability of capacitance are essential or where a precisely defined temperature coefficient is required, for example, for compensating temperature effects in the circuit. Other terms are the category temperature range, this is the range of ambient temperatures for which the capacitor has been designed to operate continuously, the rated temperature, this is the maximum ambient temperature at which the rated voltage may be continuously applied, the rated voltage, this is the maximum direct voltage or peak value of pulse voltage which may be applied continuously to a capacitor at any temperature between the lower category temperature and the rated temperature. IEC 60384-1 shall be considered regarding the marking of the capacitors. The information to be provided in marking of capacitors is usually selected from the following list and its relative importance corresponds with the ranking: nominal capacity, rated voltage, tolerance of nominal capacity, category voltage, year and month (or week) of the manufacture, name of the manufacturer and reference to the detail specification. The preferred ratings and preferred characteristics are defined in clause "Preferred ratings and characteristics". The preferred numbers of the rated voltage correspond with the standard values of series R5 in accordance with ISO 3. If other values are required they shall be taken from series R10. The sum of the d.c. voltage and the peak a.c. voltage or the peak-to-peak value of a.c. voltage (the higher value applies) applied to the capacitor must not exceed the rated voltage. The peak a.c. voltage shall not exceed the value specified by the permitted reactive power. The category voltage equals the rated voltage when the rated temperature is specified to be equal to the higher category temperature. If the higher category temperature exceeds 125 °C or the rated voltage 500 V, the category voltage shall be indicated in the detail specification. Clause "Quality assessment procedures" explains the primary stage of manufacture, namely winding the capacitor or the corresponding process, the structurally similar components, the certified records of released lots and the certification approval. The method with fixed sample sizes is described in IEC 60384-1. The sample shall represent the range of the capacitors, for which certification approval has been applied. However, it shall not necessarily be the entire range covered by the detail specification. The sample shall consist of specimens with the highest and lowest voltage and contain the lowest and highest capacity values for these voltages. If more than four rated voltages are given, an average rated voltage shall be also tested. For certification approval of a range, testing of four or six values (combinations of capacity values/rated voltages) is necessary. If the entire range covers less than four values, the number of specimens shall correspond with the required number for four values. Two or three additional specimens are allowed per value as a substitute for failures of specimens for which the manufacturer shall not be held responsible. The number of specimens indicated in group 0 applies for the case that all groups shall be tested. If this is not the case, the quantities can be reduced accordingly. If the sampling plan for the certification approval contains additional groups, the specimen quantities required for group 0 shall be supplemented by the specimens required by the additional groups. Table 4 also includes the sampling plan with fixed sample sizes for qualification approval test - Assessment level EZ. In chapter "Test and measurement procedures", preliminary drying, measuring conditions, visual examination and check of dimensions, electrical tests, temperature coefficient and temperature cycle drift, shear test and substrate bending test, resistance to soldering heat and solderability, rapid change of temperature, component solvent resistance and solvent resistance of the marking are explained. Annex A contains guidance for the specification and coding of dimensions of fixed surface mount multilayer capacitors of ceramic dielectric, Class 1; informative Annex B explains the combination of temperature coefficient and tolerance for the reference temperature of 25 °C. The following modifications have been made with respect to DIN EN 60384-21:2005-06: a) all clauses have been revised taking into consideration the entire content of the previous edition in accordance with the current shape and design requirements. b) The test voltage of 1,2 U_R at U_R ≥ 1 000 V has been added in 4.5.4 Voltage proof. c) Detail test conditions have been added in 4.7 Shear test and 4.8 Substrate bending test. d) Test conditions applying lead free solder alloy (Sn-Ag-Cu) have been included in 4.9 Resistance to soldering heat and 4.10 Solderability. e) A selection of the test conditions according to marketing needs have been stated in 4.13 Damp heat, steady state. f) The dimensions of 0402M in Annex A have been added. g) The code of the temperature coefficient and the tolerance of capacitance for the reference temperature of 25 °C have been added, see Annex B. The responsible committee is K 611 "Kondensatoren" ("Capacitors") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.