Datasheet

Package information STM8S003F3 STM8S003K3
96/103 DS7147 Rev 10
10.4 Thermal characteristics
The maximum chip junction temperature (T
Jmax
) must never exceed the values given in
Table 19: General operating conditions.
The maximum chip-junction temperature, T
Jmax
, in degrees Celsius, may be calculated
using the following equation:
T
Jmax
= T
Amax
+ (P
Dmax
x Θ
JA
)
Where:
• T
Amax
is the maximum ambient temperature in ° C
•Θ
JA
is the package junction-to-ambient thermal resistance in ° C/W
• P
Dmax
is the sum of P
INTmax
and P
I/Omax
(P
Dmax
= P
INTmax
+ P
I/Omax
)
• P
INTmax
is the product of I
DD
and V
DD
, expressed in Watts. This is the maximum chip
internal power.
• P
I/Omax
represents the maximum power dissipation on output pins, where:
P
I/Omax
= Σ (V
OL
*I
OL
) + Σ((V
DD
-V
OH)
*I
OH
), and taking account of the actual V
OL
/I
OL
and
V
OH
/I
OH
of the I/Os at low and high level in the application.
10.4.1 Reference document
JESD51-2 integrated circuits thermal test method environment conditions - natural
convection (still air). Available from www.jedec.org.
Table 55. Thermal characteristics
(1)
1. Thermal resistances are based on JEDEC JESD51-2 with 4-layer PCB in a natural convection
environment.
Symbol Parameter Value Unit
Θ
JA
Thermal resistance junction-ambient
LQFP 32 - 7 x 7 mm
60
°C/W
Thermal resistance junction-ambient
TSSOP20 - 4.4 mm
84
Thermal resistance junction-ambient
UFQFPN20 -3 x 3 mm
90