ADVANCE
CYW43570
20. Package Information
20.1 Package Thermal Characteristics
Table 40. Package Thermal Characteristicsa
Characteristic
JA (°C/W) (value in still air)
JB (°C/W)
Value
26.38
8.37
9.94
6.12
12.62
125
JC (°C/W)
(°C/W)
JT
(°C/W)
JB
Maximum Junction Temperature T (°C)
j
Maximum Power Dissipation (W)
2.46
a. 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 = 1.53W continuous dissipation.
20.2 Junction Temperature Estimation and PSI Versus Theta
JT
JC
The package thermal characterization parameter PSI ( ) yields a better estimation of actual junction temperature (T ) than using
JT
JT
J
the junction-to-case thermal resistance parameter Theta (JC). The reason for this is that JC is based on the assumption that all
JC
the power is dissipated through the top surface of the package case. In actual applications, however, some of the power is dissipated
through the bottom and sides of the package. takes into account the power dissipated through the top, bottom, and sides of the
JT
package. The equation for 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 Table 22.
Document Number: 002-15054 Rev. *I
Page 88 of 94
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