Subcommittee 3D DATA SETS FOR LIBRARIES

SC 3D Experience report for implementing IEC – Conventions and guidelines Cape Town, (Cape Town/Dijkstra)4 Addie Dijkstra Secretary, IEC SC3D

SC 3D 3(Cape Town/Dijkstra)4: 3 Basic contents  IEC data dictionary at PSC  Need for conventions and guidelines  Conventions for definition  Conventions for naming  Conventions for symbol  Some questions to you

SC 3D 3(Cape Town/Dijkstra)4: 4 IEC data dictionary at PSC Philips Semiconductors SPIDER program Type of information to be managed: Any product information or knowledge required during any of the stages of the customer’s product/business creation process Current status: Pilot phase – First 700 products defined in the product library based on data dictionary before end 2005

SC 3D 3(Cape Town/Dijkstra)4: 5 Goals  Capture product parametric information at the source [and only once]  Use resulting content to generate :  Product information web pages and datasheets  Selection guides  Electronic data exchange e.g. RosettaNet PIP 2A10  …

SC 3D 3(Cape Town/Dijkstra)4: 6 Datasheet Rapidly growing complexity  Largest datasheet 1996: 125 pages  Largest datasheet 2002: 650 pages with 521 device characteristics!  Percentage of web visitors downloading datasheets: 87%  Estimated cost to re-create all existing datasheets at current rates: EUR XXX,000,000

SC 3D 3(Cape Town/Dijkstra)4: 7 Dictionary of data element types Dictionary and library information model is based on:  RosettaNet Dictionary Architecture model, compliant with ISO/IEC information model (IEC ) Dictionary content:  IEC-61360, Philips proprietary and possibly RNTD Dictionary will be used as (a.o.) a mechanism to enforce standards and consistency

SC 3D 3(Cape Town/Dijkstra)4: 8 Need for conventions and guidelines Which standards apply  Information model  IEC  DET attributes and their definitions  ISO/IEC , IEC  Conventions for writing definitions  ISO/IEC  Conventions for writing names  ISO/IEC (includes guidelines for writing naming conventions and an example convention)  Conventions for writing symbols  ISO 31, IEC 60027, 60747, 60748

SC 3D 3(Cape Town/Dijkstra)4: 9 Conventions for writing definitions ISO/IEC A data definition shall [requirements]: a) be stated in the singular b) state what the concept is, not only what it is not c) be stated as a descriptive phrase or sentence(s) d) contain only commonly understood abbreviations e) be expressed without embedding definitions of other data or underlying concepts

SC 3D 3(Cape Town/Dijkstra)4: 10 Conventions for writing definitions ISO/IEC A data definition should [recommendations]: a) state the essential meaning of the concept b) be precise and unambiguous c) be concise d) be able to stand alone e) be expressed without embedding rationale, functional usage, or procedural information f) avoid circular reasoning g) use the same terminology and consistent logical structure for related definitions h) be appropriate for the type of metadata item being defined

SC 3D 3(Cape Town/Dijkstra)4: 11 Conventions for writing names ISO/IEC Includes guidelines for writing structured naming conventions:  Semantic rules enable meaning to be conveyed;  Syntactic rules relate components in a consistent, specified order;  Lexical (word form and vocabulary) rules reduce redundancy and increase precision;

SC 3D 3(Cape Town/Dijkstra)4: 12 Naming convention for DETs A data element type name shall: a) be stated in the singular b) be written in lower case with the exception of particular abbreviations and acronyms that are commonly written in upper case c) contain only commonly understood abbreviations and acronyms * * Managed by a Philips Semiconductors exceptions list for allowed abbreviations and acronyms

SC 3D 3(Cape Town/Dijkstra)4: 13 Specific DET naming rules Distinguish between type of DET  Mechanical quantitative data element types  start with the concept or object being specified followed by the measured aspect such as: length, height, diameter  Non-quantitative data element types  start with the concept or object being specified followed by a qualifier such as: type, code, name, description  Electrical quantitative data element types

SC 3D 3(Cape Town/Dijkstra)4: 14 Naming convention for DETs Electrical quantitative data element types  reflect the electrical symbol in words reading in reverse order;  start with the concept or object being specified, followed by the measured quantity such as: voltage, current, capacitance, temperature;  The concept or object is possibly preceded by one or more qualifiers such as: maximum, peak, average, total;  The measured quantity is possibly followed by a non-quantitative condition such as: from junction to lead;

SC 3D 3(Cape Town/Dijkstra)4: 15 Example REMARK – The allowed non-quantitative conditions are managed in a Philips Semiconductors non-quantitative conditions list. Only those that are approved shall be used. QualifierConceptMeasured quantity Non-quantitative condition maximuminputvoltage ambienttemperature initialjunctiontemperature maximum repetitive peak off-statevoltage transientthermalimpedancefrom junction to lead

SC 3D 3(Cape Town/Dijkstra)4: 16 Conventions for writing symbols A symbol shall: a) use a consistent and approved set of characters; b) contain only commonly understood abbreviations; c) use parentheses “()” to separate adjacent symbol parts that are written in the same case (upper or lower);* d) not exceed a length of 17 characters (not including mark-up); * In general, the first part of subscript is not enclosed in parentheses

SC 3D 3(Cape Town/Dijkstra)4: 17 Conventions for writing symbols A symbol should: a) be concise - use the minimum number of letters b) use consistent logical structure for related symbols c) reflect the words of the data element type name reading in reverse order d) derive the first symbol letter from the measured quantity (its basic letter symbol) which relates to the specified unit

SC 3D 3(Cape Town/Dijkstra)4: 18 Some questions Questions:  What can TC3 apply from what is already defined in for writing definitions?  Could TC3 benefit further from joined conventions on naming and writing symbols?  Could IEC benefit from a document such as a guide on Conventions for naming, definition and symbols stating the basic principles?

SC 3D Thank you for your attention.