Package information
Dim.
STM8S903K3 STM8S903F3
mm
Min
inches(1)
Typ
Max
10.650
Min
Typ
Max
0.4193
H
10.000
0.3937
0.0098
0.0157
0.0°
h
0.250
0.400
0.0°
0.750
1.270
8.0°
0.0295
0.0500
8.0°
L
k
ddd
0.100
0.0039
(1) Values in inches are converted from mm and rounded to 4 decimal digits
11.8
Thermal characteristics
The maximum chip junction temperature (TJ max) must never exceed the values given in
Operating conditions.
The maximum chip-junction temperature, TJmax, in degrees Celsius, may be calculated using
the following equation:
TJmax = TAmax + (PDmax x ΘJA
Where:
)
TAmax is the maximum ambient temperature in °C
•
•
•
•
ΘJA is the package junction-to-ambient thermal resistance in °C/W
PDmax is the sum of PINTmax and PI/Omax (PDmax = PINTmax + PI/Omax
)
PINTmax is the product of IDD andVDD, expressed in Watts. This is the maximum chip internal
power.
PI/Omax represents the maximum power dissipation on output pins
Where:
•
PI/Omax =Σ (VOL*IOL) + Σ((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 60: Thermal characteristics
Symbol
ΘJA
Parameter(1)
Value
Unit
110
Thermal resistance junction-ambient
TSSOP20 - 4 x 4 mm
°C/W
ΘJA
20
Thermal resistance junction-ambient
SO20W - 300 mils
°C/W
102/116
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