AS1369 datasheet(16/22 Pages) AMSCO

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AS1369

Datasheet - Application In form atio n

8.4 Junction Temperature

Under all operating conditions, the maximum junction temperature should not be allowed to exceed 125°C (unless otherwise specified in the

datasheet). Limiting the maximum junction temperature requires knowledge of the heat path from junction to case (

JC°C/W fixed by the IC

manufacturer), and adjustment of the case to ambient heat path (

CA°C/W) by manipulation of the PCB copper area adjacent to the IC position.

Figure 48. Package Physical Arrangements

Figure 49. Steady State Heat Flow Equivalent Circuit

Total Thermal Path Resistance:

JA = RJC + RCS + RSA

(EQ 7)

Junction Temperature (TJ ºC) is determined by:

TJ = (PD(MAX) x RJA) + TAMB ºC

(EQ 8)

Chip

PCB

Package

Transfer Layer

CS-WLP Package

Solder Balls

Junction

TJ°C

Package

TC°C

PCB/Heatsink

TS°C

Ambient

TA°C

Chip

Power

JC

CS

SA

AS1369 Datasheet(PDF) 16 Page - ams AG