Package characteristics
STM8S207xx, STM8S208xx
11.2
Thermal characteristics
The maximum chip junction temperature (T
) must never exceed the values given in
Jmax
Table 18: General operating conditions on page 56.
The maximum chip-junction temperature, T
using the following equation:
, in degrees Celsius, may be calculated
Jmax
T
= T
+ (P
x Θ )
Jmax
Amax
Dmax JA
Where:
●
●
●
●
T
is the maximum ambient temperature in °C
is the package junction-to-ambient thermal resistance in ° C/W
Amax
Θ
JA
P
is the sum of P
and P
(P
= P
+ P
)
I/Omax
Dmax
INTmax
I/Omax
Dmax
INTmax
P
is the product of I and V , expressed in Watts. This is the maximum chip
INTmax
DD
DD
internal power.
●
P
P
represents the maximum power dissipation on output pins, where:
I/Omax
I/Omax
= Σ (V *I ) + Σ((V -V *I ), and taking account of the actual V /I and
OL OL
DD OH) OH
OL OL
V
/I of the I/Os at low and high level in the application.
OH OH
(1)
Table 57. Thermal characteristics
Symbol
Parameter
Value
Unit
Thermal resistance junction-ambient
LQFP 80 - 14 x 14 mm
Θ
38
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
JA
Thermal resistance junction-ambient
LQFP 64 - 14 x 14 mm
Θ
45
46
57
54
60
JA
Thermal resistance junction-ambient
LQFP 64 - 10 x 10 mm
Θ
JA
Thermal resistance junction-ambient
LQFP 48 - 7 x 7 mm
Θ
JA
Thermal resistance junction-ambient
LQFP 44 - 10 x 10 mm
Θ
JA
Thermal resistance junction-ambient
LQFP 32 - 7 x 7 mm
Θ
JA
1. Thermal resistances are based on JEDEC JESD51-2 with 4-layer PCB in a natural convection
environment.
11.2.1
Reference document
JESD51-2 integrated circuits thermal test method environment conditions - natural
convection (still air). Available from www.jedec.org.
96/103
Doc ID 14733 Rev 9
STMICROELECTRONICS [ ST ]
