IEC TR 63378-1-2021 pdf free download – Thermal standardization on semiconductor packages – Part 1: Thermal resistance and thermal parameter of BGA, QFP type semiconductor packages.
This part of lEC 63378 specifies the terms and definitions that are commonly used for thermalcharacteristics of BGA and QFP type semiconductor packages, and guidelines to use thesethermal characteristics.
2Normative references
The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references, only the edition cited applies.For undated references,the latest edition of the referenced document (including anyamendments) applies.
IEC 60191-4，Mechanical standardization of semiconductor devices – Part 4:Coding systemand classification into forms of package outlines for semiconductor device packages
3 Terms and definitions
For the purposes of this document,the terms and definitions given in lEC 60191-4 and thefollowing apply.
ISO and lEC maintain terminological databases for use in standardization at the followingaddresses:
. IEC Electropedia: available at http://www.electropedia.orgl
. Iso Online browsing platform: available at http://www.iso.org/obp3.1 Terms and letter symbols related to temperature (unit [C or K])3.1.1
ambient air temperatureTA
temperature of ambient air at location adequately distant from the package (see Figure 1)
Note 1 to entry: Conceptually, it refers to an ambient air temperature at a location that is not affected by thesemiconductor package to be measured.
3.1.2
junction temperatureTJ
temperature of at an arbitrary position of the chip (see Figure 1)
Note 1 to entry: Especially when there is no specification, it is considered as the centre of a chip.
Note 2 to entry: Junction refers to the junction area of a semiconductor. Assuming that heat is generated at thejunction of p-type and n-type, temperature at the junction becomes high and is used as representing temperature forsemiconductor devices.Because there are many junctions built into a real chip, the term junction is usedsynonymously as the chip. The location is commonly placed at the centre of the circuit surface of the chip, althoughlocation dependence may be taken into consideration for chips requiring high power consumption.
3.1.3
case temperature
T C
temperature at an arbitrary position on the surface of a package (see Figure 1 )
Note 1 to entry: Especially when there is no specification, it is considered as the centre of a chip upper part.
3.1.4
top temperature
T T
temperature at the centre of the package’s upper surface (see Figure 1 )
Note 1 to entry: Defined as T T due to T C used as definition for special surface at back of package of power device, etc.
For normal package such as BGA, T C and T T are used synonymously.
3.1.5
board temperature
T B
temperature of the board which is distant from an arbitrary end of a package 1 mm
(see Figure 1 )
3.2 Terms and letter symbols related to thermal characteristics
3.2.1
thermal resistance
quotient of the difference between the virtual temperature of the device and the temperature of a stated external reference point, by the steady-state power dissipation in the device (see Figure 2)
[SOURCE: IEC 60050-521 :2002, 521 -05-1 3, modified – Figure 2 and Note 1 to entry have been added.]
3.2.1 .1
thermal resistance from junction-to-ambient
R th(j-a)
θ JA
thermal resistance between chip (junction) and ambient air (see Figure 1 )IEC TR 63378-1 pdf download.