STMicroelectronics STM32F038C6 - Page 97

DocID026079 Rev 3 97/102
STM32F038x6 Package information
98
Assuming the following application conditions:
Maximum ambient temperature T
Amax
= 100 °C (measured according to JESD51-2),
I
DDmax
= 20 mA, V
DD
= 3.5 V, maximum 20 I/Os used at the same time in output at low
level with I
OL
= 8 mA, V
OL
= 0.4 V
P
INTmax =
20 mA × 3.5 V= 70 mW
P
IOmax = 20
× 8 mA × 0.4 V = 64 mW
This gives: P
INTmax
= 70 mW and P
IOmax
= 64 mW:
P
Dmax =
70
+
64 = 134 mW
Thus: P
Dmax
= 134 mW
Using the values obtained in Table 66 T
Jmax
is calculated as follows:
– For LQFP48, 55 °C/W
T
Jmax
= 100 °C + (55 °C/W × 134 mW) = 100 °C + 7.37 °C = 107.37 °C
This is above the range of the suffix 6 version parts (–40 < T
J
< 105 °C).
In this case, parts must be ordered at least with the temperature range suffix 7 (see
Section 8: Part numbering) unless we reduce the power dissipation in order to be able to
use suffix 6 parts.