Table of Contents
Advertisement
20. Package Information
20.1 Package Thermal Characteristics
Table 54. Package Thermal Characteristics
(°C/W) (value in still air)
JA
(°C/W)
JB
(°C/W)
JC
(°C/W)
JT
(°C/W)
JB
Maximum Junction Temperature T
Maximum Power Dissipation (W)
1.
No heat sink, TA = 70°C. This is an estimate, based on a 4-layer PCB that conforms to EIA/JESD51–7 (101.6 mm × 101.6 mm × 1.6 mm) and P = specified
power maximum continuous power dissipation.
20.2 Junction Temperature Estimation and PSI
Package thermal characterization parameter PSI–J
the junction-to-case thermal resistance parameter Theta–J
sipated through the top surface of the package case. In actual applications, some of the power is dissipated through the bottom and
sides of the package.
JT
calculating the device junction temperature is:
TJ = TT + P x JT
Where:
T
= Junction temperature at steady-state condition (°C)
■
J
T
= Package case top center temperature at steady-state condition (°C)
■
T
P = Device power dissipation (Watts)
■
= Package thermal characteristics; no airflow (°C/W)
■
JT
20.3 Environmental Characteristics
For environmental characteristics data, see
Document Number: 002-14949 Rev. *G
PRELIMINARY
1
Characteristic
(°C)
j
T
takes into account power dissipated through the top, bottom, and sides of the package. The equation for
Table 24, "Environmental
Versus THETA
JT
JC
(
) yields a better estimation of actual junction temperature (T
JT
(
). The reason for this is that
C
JC
Ratings,".
CYW43353
WLBGA
32.9
2.56
0.98
3.30
9.85
125
1.119
) versus using
J
assumes that all the power is dis-
JC
Page 107 of 113
Advertisement
Table of Contents
