STR750FXX STMICROELECTRONICS [STMicroelectronics], STR750FXX Datasheet - Page 78

• Manufacturer Part Number: STR750FXX
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Package characteristics
6.2
78/81
Thermal characteristics
The average chip-junction temperature, T
The average chip-junction temperature, T
following equation:
T
Where:
Most of the time for the applications P
P
and/or memories.
An approximate relationship between P
P
Therefore (solving equations 1 and 2):
K = P
where:
Table 48.
J
I/O
D
= T
= K / (T
Symbol
may be significant if the device is configured to drive continuously external modules
–
–
–
–
–
–
D
Θ
Θ
Θ
Θ
A
JA
JA
JA
JA
x (T
+ (P
T
Θ
P
P
Power.
P
K is a constant for the particular part, which may be determined from equation (3)
by measuring P
of P
value of T
A
J
D
INT
I/O
A
JA
D
+ 273°C) (2)
is the Ambient Temperature in °C,
Thermal characteristics
+ 273°C) + Θ
is the sum of P
D
x Θ
is the Package Junction-to-Ambient Thermal Resistance, in ° C/W,
represents the Power Dissipation on Input and Output Pins;
is the product of I
and T
Thermal Resistance Junction-Ambient
LQFP 100 - 14 x 14 mm / 0.5 mm pitch
Thermal Resistance Junction-Ambient
LQFP 64 - 10 x 10 mm / 0.5 mm pitch
Thermal Resistance Junction-Ambient
LFBGA 64 - 8 x 8 x 1.7mm
Thermal Resistance Junction-Ambient
LFBGA 100 - 10 x 10 x 1.7mm
JA
A
)(1)
.
J
may be obtained by solving equations (1) and (2) iteratively for any
D
JA
(at equilibrium) for a known T
INT
x P
and P
DD
D
2
(3)
Parameter
and V
I/O
I/O
D
(P
< P
STR750Fxx STR751Fxx STR752Fxx STR755Fxx
DD
J
and T
J
, in degrees Celsius, may be calculated using the
D
must never exceed 125° C.
, expressed in Watts. This is the Chip Internal
INT
= P
J
and may be neglected. On the other hand,
INT
(if P
+ P
I/O
I/O
is neglected) is given by:
A.
),
Using this value of K, the values
Value
46
45
58
41
°C/W
°C/W
°C/W
°C/W
Unit