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STM32L151x6/8/B, STM32L152x6/8/B
Package characteristics
128
7.2 Thermal
characteristics
The maximum chip-junction temperature, T
J
max, in degrees Celsius, may be calculated
using the following equation:
T
J
max = T
A
max + (P
D
max ×
Θ
JA
)
Where:
•
T
A
max is the maximum ambient temperature in
°
C,
•
Θ
JA
is the package junction-to-ambient thermal resistance, in
°
C/W,
•
P
D
max is the sum of P
INT
max and P
I/O
max (P
D
max = P
INT
max + P
I/O
max),
•
P
INT
max is the product of I
DD
and
V
DD
, expressed in Watts. This is the maximum chip
internal power.
P
I/O
max represents the maximum power dissipation on output pins where:
P
I/O
max
=
Σ
(V
OL
× I
OL
) +
Σ
((V
DD
– V
OH
) × I
OH
),
taking into account the actual V
OL
/ I
OL
and V
OH
/ I
OH
of the I/Os at low and high level in the
application.
Table 69. Thermal characteristics
Symbol
Parameter
Value
Unit
Θ
JA
Thermal resistance junction-ambient
BGA100 - 7 x 7 mm
59
°C/W
Thermal resistance junction-ambient
LQFP100 - 14 x 14 mm / 0.5 mm pitch
46
Thermal resistance junction-ambient
TFBGA64 - 5 x 5 mm
65
Thermal resistance junction-ambient
LQFP64 - 10 x 10 mm / 0.5 mm pitch
45
Thermal resistance junction-ambient
LQFP48 - 7 x 7 mm / 0.5 mm pitch
55
Thermal resistance junction-ambient
UFQFPN48 - 7 x 7 mm / 0.5 mm pitch
16