IEC TR 63378-1:2021

IEC TR 63378-1 ®
Edition 1.0 2021-12
TECHNICAL
REPORT
colour
inside
Thermal standardization on semiconductor packages –
Part 1: Thermal resistance and thermal parameter of BGA, QFP type
semiconductor packages
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IEC TR 63378-1 ®
Edition 1.0 2021-12
TECHNICAL
REPORT
colour
inside
Thermal standardization on semiconductor packages –

Part 1: Thermal resistance and thermal parameter of BGA, QFP type

semiconductor packages
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.01 ISBN 978-2-8322-1062-3

– 2 – IEC TR 63378-1:2021 © IEC 2021
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
3.1 Terms and letter symbols related to temperature (unit [°C or K]) . 5
3.2 Terms and letter symbols related to thermal characteristics . 6
4 Accuracy of θ . 10
JA
4.1 Variation of θ . 10
JA
4.1.1 General . 10
4.1.2 Analysis model . 10
4.1.3 Simulation conditions (typical values) . 11
4.1.4 Evaluation items and standards . 11
4.1.5 Evaluation results . 12
4.1.6 Summary . 17
4.2 Discrepancy of θ . 18
JA
5 Guideline for thermal design . 19
Bibliography . 20

Figure 1 – Definition of temperature . 6
Figure 2 – Definition of thermal resistance . 7
Figure 3 – Thermal resistance. 8
Figure 4 – Thermal resistance and thermal characterization parameter . 9
Figure 5 – Thermal characterization parameter . 10
Figure 6 – Simulation conditions . 11
Figure 7 – θ
dependence on board remaining copper rate (BGA) . 12
JA
Figure 8 – θ dependence on remaining copper rate (LQFP) . 13
JA
Figure 9 – θ dependence on ambient air temperature T (BGA) . 14
JA A
Figure 10 – θ dependence on ambient air temperature T (LQFP) . 15
JA A
Figure 11 – θ dependence on power dissipation (BGA). 16
JA
Figure 12 – θ dependence on power dissipation (LQFP) . 17
JA
Figure 13 – Influence items and their impact on θ . 17
JA
Figure 14 – The gap of θ by the difference of the environment . 19
JA
Table 1 – Evaluation items and evaluation parameters . 11

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
THERMAL STANDARDIZATION ON SEMICONDUCTOR PACKAGES –

Part 1: Thermal resistance and thermal parameter of BGA,
QFP type semiconductor packages

FOREWORD
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IEC TR 63378-1 has been prepared by subcommittee 47D: Semiconductor devices packaging,
of IEC technical committee 47: Semiconductor devices. It is a Technical Report.
The text of this Technical Report is based on the following documents:
Draft Report on voting
47D/928/DTR 47D/935/RVDTR
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this Technical Report is English.

– 4 – IEC TR 63378-1:2021 © IEC 2021
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 63378 series, published under the general title Thermal
standardization on semiconductor packages, 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 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.
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THERMAL STANDARDIZATION ON SEMICONDUCTOR PACKAGES –

Part 1: Thermal resistance and thermal parameter of BGA,
QFP type semiconductor packages

1 Scope
This part of IEC 63378 specifies the terms and definitions that are commonly used for thermal
characteristics of BGA and QFP type semiconductor packages, and guidelines to use these
thermal characteristics.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 60191-4, Mechanical standardization of semiconductor devices – Part 4: Coding system
and classification into forms o
...