CD00191174 Datasheet, PDF (105/112 Pages) STMicroelectronics – High-density access line, ARM-based 32-bit MCU

STM32F101xC, STM32F101xD, STM32F101xE
Package characteristics
6.2.2
Evaluating the maximum junction temperature for an application
When ordering the microcontroller, the temperature range is specified in the ordering
information scheme shown in Table 65: Ordering information scheme.
Each temperature range suffix corresponds to a specific guaranteed ambient temperature at
maximum dissipation and, to a specific maximum junction temperature. Here, only
temperature range 6 is available (–40 to 85 °C).
The following example shows how to calculate the temperature range needed for a given
application, making it possible to check whether the required temperature range is
compatible with the STM32F10xxx junction temperature range.
Example: High-performance application
Assuming the following application conditions:
Maximum ambient temperature T_Amax = 82 °C (measured according to JESD51-2),
I_DDmax = 50 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 and maximum 8 I/Os used at the same time in output
mode at low level with I_OL = 20 mA, V_OL= 1.3 V
P_INTmax = 50 mA × 3.5 V= 175 mW
P_IOmax = 20 × 8 mA × 0.4 V + 8 × 20 mA × 1.3 V = 272 mW
This gives: P_INTmax = 175 mW and P_IOmax = 272 mW
P_Dmax = 175 + 272 = 447 mW
Thus: P_Dmax = 447 mW
Using the values obtained in Table 65 T_Jmax is calculated as follows:
– For LQFP64, 45 °C/W
T_Jmax = 82 °C + (45 °C/W × 447 mW) = 82 °C + 20.1 °C = 102.1 °C
This is within the junction temperature range of the STM32F10xxx (–40 < T_J < 105 °C).
Figure 60. LQFP64 P_D max vs. T_A
700
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0
65 75 85 95 105 115
T_A (°C)
Suffix 6
Doc ID 14610 Rev 8
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