STM8S207xx, STM8S208xx
Package characteristics
11.2.2
Selecting the product temperature range
When ordering the microcontroller, the temperature range is specified in the order code (see
(1)
Figure 49: STM8S207xx/208xx performance line ordering information scheme on
page 100).
The following example shows how to calculate the temperature range needed for a given
application.
Assuming the following application conditions:
●
●
●
Maximum ambient temperature T
= 82 °C (measured according to JESD51-2)
Amax
I
= 15 mA, V = 5.5 V
DD
DDmax
Maximum eight standard I/Os used at the same time in output at low level with I = 10
OL
mA, V = 2 V
OL
●
●
Maximum four high sink I/Os used at the same time in output at low level with I = 20
OL
mA, V = 1.5 V
OL
Maximum two true open drain I/Os used at the same time in output at low level with
I
= 20 mA, V = 2 V
OL
OL
P
P
15 mA x 5.5 V = 82.5 mW
INTmax =
(10 mA x 2 V x 8 ) + (20 mA x 2 V x 2) + (20 mA x 1.5 V x 4) = 360 mW
IOmax =
This gives: P
= 82.5 mW and P
360 mW:
IOmax
INTmax
P
= 82.5 mW + 360 mW
Dmax
Thus: P
= 443 mW
Dmax
Using the values obtained in Table 57: Thermal characteristics on page 96 T
is
Jmax
calculated as follows for LQFP64 10 x 10 mm = 46 °C/W:
T
= 82 °C + (46 °C/W x 443 mW) = 82 °C + 20 °C = 102 °C
Jmax
This is within the range of the suffix 6 version parts (-40 < T < 105 °C).
J
In this case, parts must be ordered at least with the temperature range suffix 6.
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