DIN EN 61240:2013-05

In this second edition of DIN EN 61240 the enclosures of quartz crystal resonators and oscillators are uniformly specified. This standard provides general rules for drawing all dimensional and geometrical characteristics of a surface-mounted piezoelectric device enclosure in order to ensure comparability and inter-changeability of all outline drawings of surface-mounted devices (referred to in this standard as SMD) for frequency control and selection. Regarding the current situation of many quartz crystal device suppliers, many suppliers use their own enclosure layouts in their catalogues. For the convenience of consumers, general rules of enclosure layout and definition of size shall be uniformly specified. In the first edition, layout rules of outline drawings of SMD devices were based on IEC 60191-6 and applied to semi-conductive devices. However, there are several specific rules for quartz devices. In this edition, the general rules for outline drawings of SMD enclosures for quartz crystal devices are included, taking account of the ISO layout rules (ISO 1101, ISO 5456-2, and ISO 128-30). The newly proposed general rules of outline drawings for three types of surface-mounted devices are shown in sheets included as examples. The difference from the previous version of outline drawings is that one set of drawings consists of four views: the view from above, the front view, the view from the right, and the view from below. Furthermore, the definition of the drawings has been changed. Firstly, ceramic enclosure is specifically defined. Secondly, the reference line of the package is defined as shown in the sheets. Thirdly, geometrical dimensions of the package have been further simplified compared to the previous edition. These corrections are shown in Annexes A and B of this standard. The SMD piezoelectric devices are classified into three types of packages depending on the structure of the terminal leads. a) Leaded type: the folded ends of the terminal leads are turned away from the body. b) Folded-leads type: the folded ends of the terminal lead are turned towards the body. c) Leadless type: terminal pads only are present on the body instead of terminal leads. Additional clauses of the standard include the title of the outline drawing, composition of the outline drawing, requirements for terminal leads, requirements for the terminal land area and connections of terminal leads. Informative Annex A describes miniaturized leadless ceramic enclosures of piezoelectric devices (SMD) for frequency control and selection. Informative Annex B contains an example of terminal connections for surface-mounted piezoelectric devices (SMD) for frequency control and selection. The responsible committee is K 642 "Piezoelektrische Bauteile zur Frequenzstabilisierung und -selektion" ("Piezoelectric and dielectric devices for frequency control and selection") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.