IEC TR 63238-1:2019

IEC TR 63238-1 ®
Edition 1.0 2019-07
TECHNICAL
REPORT
colour
inside
Process management for avionics – Electronics design –
Part 1: Electrical signal properties, naming conventions and interface control
document (ICD)
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IEC TR 63238-1 ®
Edition 1.0 2019-07
TECHNICAL
REPORT
colour
inside
Process management for avionics – Electronics design –

Part 1: Electrical signal properties, naming conventions and interface control

document (ICD)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 03.100.50; 31.020; 49.060 ISBN 978-2-8322-7187-2

– 2 – IEC TR 63238-1:2019  IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
Terms and definitions . 5
Abbreviated terms . 6
4 ICD description . 6
General . 6
Electrical interface . 7
ICD specification format . 7
General . 7
Format of the ICD specification . 7
ICD content . 8
Annex A (informative)  Example of an ICD . 13
Bibliography . 15

Figure 1 – Example of an electronic schematic including an electrical interface . 7
Figure 2 – Signal “Sig1”: Sinusoidal wave . 10
Figure 3 – Signal “Sig2”: Rectangular wave . 11
Figure 4 – Signal “Sig3”: Symmetrical triangular wave . 11
Figure 5 – Signal “Sig4”: Trapezoidal cut wave . 11
Figure 6 – Signal “Sig5”: Upper half sine wave . 11
Figure 7 – Signal “Sig6”: Triangular align right . 11
Figure A.1 – Example of an ICD . 13

Table 1 – Examples for sources and loads . 7
Table 2 – Typical ICD specification table header . 8
Table 3 – Typical ICD file . 8
Table 4 – Source or load type “L1” . 10
Table 5 – Shape of signal “L2” . 10
Table 6 – Columns for describing the characteristics of each signal shape . 12
Table A.1 – Example for ICD data . 14

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PROCESS MANAGEMENT FOR AVIONICS –
ELECTRONICS DESIGN –
Part 1: Electrical signal properties, naming conventions and interface
control document (ICD)
FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a Technical Report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 63238-1, which is a Technical Report, has been prepared by IEC technical
committee 107: Process management for avionics.
The text of this Technical Report is based on the following documents:
Draft TR Report on voting
107/351/DTR 107/356/RVDTR
Full information on the voting for the approval of this Technical Report can be found in the
report on voting indicated in the above table.

– 4 – IEC TR 63238-1:2019  IEC 2019
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 63238 series, published under the general title Process
management for avionics – Electronics design, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
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PROCESS MANAGEMENT FOR AVIONICS –
ELECTRONICS DESIGN –
Part 1: Electrical signal properties, naming conventions and interface
control document (ICD)
1 Scope
This part of IEC 63238 provides information and a template to create an interface control
document (ICD) for any project which includes electronic assemblies, such as electronic
circuit card assemblies (CCAs) or electronic devices, connected together. This document
proposes electrical signal naming conventions when interfacing electronic assemblies, and an
example containing seven signal naming conventions is included. This document supports
original equipment manufacturers (OEMs) in the preparation and maintenance of their
electronic assemblies interfaces and integration specifications to avoid misunderstanding of
signals which can cause unnecessary design and/or integration errors, and testing
complications.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
interface control document
ICD
document which defines for each electronic signal its electrical properties value and naming
Note 1 to entry Typical electronic signal examples include DC voltage, 5 V, 3,3 V.
Note 2 to entry Typical electrical property values include sine wave, rectangular wave.
3.1.2
electronic assembly
electrical or electronic device that is not subject to disassembly without destruction or
impairment of design use
EXAMPLE Electronic circuit cards or modules, displays, storage devices, printers, laptop computer, electro/optical
devices, etc.
[SOURCE: IEC TS 62239-2:2017, 3.1.20]

– 6 – IEC TR 63238-1:2019  IEC 2019
3.1.3
circuit card assembly
CCA
functional electronic product based on a printed circuit board (PCB) which supports and
connects electronic or electrical components
Note 1 to entry: Components are generally soldered onto the PCB to both electrically connect and mechanically
fasten them to it.
Note
...