STM32F301x6 STM32F301x8
Package characteristics
7.2
Thermal characteristics
The maximum chip junction temperature (TJmax) must never exceed the values given in
Table 23: General operating conditions.
The maximum chip-junction temperature, TJ max, in degrees Celsius, may be calculated
using the following equation:
TJ max = TA max + (PD max x ï‘JA)
Where:
 TA max is the maximum ambient temperature in °C,
ï‚· ï‘JA is the package junction-to-ambient thermal resistance, in ï‚°C/W,
ï‚· PD max is the sum of PINT max and PI/O max (PD max = PINT max + PI/Omax),
ï‚· PINT max is the product of IDD and VDD, expressed in Watts. This is the maximum chip
internal power.
PI/O max represents the maximum power dissipation on output pins where:
PI/O max = ï“ï€ (VOL × IOL) + ï“((VDD – VOH) × IOH),
taking into account the actual VOL / IOL and VOH / IOH of the I/Os at low and high level in the
application.
Table 78. Package thermal characteristics
Symbol
Parameter
Value
Thermal resistance junction-ambient
LQFP64 - 10 × 10 mm / 0.5 mm pitch
45
Thermal resistance junction-ambient
LQFP48 - 7 × 7 mm
55
ï‘JA
Thermal resistance junction-ambient
WCSP49 - 3.4 x 3.4 mm
49
Thermal resistance junction-ambient
UFQFN32 - 5 x 5 mm
37
Unit
°C/W
7.2.1
Reference document
JESD51-2 Integrated Circuits Thermal Test Method Environment Conditions - Natural
Convection (Still Air). Available from www.jedec.org
DocID025146 Rev 3
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