STM8T141 Datasheet, PDF (41/50 Pages) STMicroelectronics – On-chip integrated voltage regulator

STM8T141
Package characteristics
10.2
10.2.1
Package thermal characteristics
The maximum chip junction temperature (T_Jmax) must never exceed the values given in
Table 12: Operating characteristics on page 30.
The maximum chip-junction temperature, T_Jmax, in degrees Celsius, may be calculated
using the following equation:
T_Jmax = T_Amax + (P_Dmax x _JA)
Where:
● T_Amax is the maximum ambient temperature in C
● _JA is the package junction-to-ambient thermal resistance in C/W
● P_Dmax is the sum of P_INTmax and P_I/Omax (P_Dmax = P_INTmax + P_I/Omax)
● P_INTmax is the product of I_DD and V_DD, expressed in Watts. This is the maximum chip
internal power.
● P_I/Omax represents the maximum power dissipation on output pins
Where:
P_I/Omax = (V_OL*I_OL) + ((V_DD-V_OH)*I_OH), 
taking into account the actual V_OL/I_OL and V_OH/I_OH of the I/Os at low and high level in
the application.
Table 25. Thermal characteristics⁽¹⁾
Symbol
Parameter
Value
_JA
Thermal resistance junction-ambient
SO8 (Narrow)
130
_JA
Thermal resistance junction-ambient
UFDFPN 8 (2 x 3 mm)
120
1. Thermal resistances are based on JEDEC JESD51-2 with 4-layer PCB in a natural convection
environment.
Unit
°C/W
°C/W
Reference document
JESD51-2 integrated circuits thermal test method environment conditions - natural
convection (still air). Available from www.jedec.org.
Doc ID 15699 Rev 7
41/50