STM32WB55xx STM32WB35xx
Package information
Note:
With this given PD max user can find the TA max allowed for a given device temperature
range (order code suffix 7).
Suffix 7: TA max = TJ max - (47 °C / W × 447 mW) = 125 °C - 21 °C = 103 °C
Example 2: High-temperature application
Using the same rules, it is possible to address applications running at high ambient
temperatures with a low dissipation, as long as junction temperature TJ remains within the
specified range.
Assuming the following application conditions:
Maximum ambient temperature TA max = 100 °C (measured according to JESD51-2),
IDD max = 50 mA, VDD = 3.5 V, maximum 20 I/Os used at the same time in output at
low level with IOL = 8 mA, VOL= 0.4 V
PINT max = 50 mA × 3.5 V = 175 mW
PIO max = 20 × 8 mA × 0.4 V = 64 mW
This gives: PINTmax = 175 mW and PIO max = 64 mW
PD max = 175 + 64 = 239 mW
Thus: PD max = 239 mW
Using the values obtained in Table 106 TJ max is calculated as follows:
– For UFQFPN48, 24.9 °C / W
TJ max = 100 °C + (24.9 °C / W × 239 mW) = 100 °C + 6 °C = 106 °C
This is above the range of the suffix 6 version parts (–40 < TJ < 105 °C).
In this case, parts must be ordered at least with the temperature range suffix 7 (see
Section 8), unless user reduces the power dissipation to be able to use suffix 6 parts.
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