at32uc3b0512-z2ues ATMEL Corporation, at32uc3b0512-z2ues Datasheet - Page 637

• Manufacturer Part Number: at32uc3b0512-z2ues
• Description: 32-bit Avr Microcontroller
• Manufacturer: ATMEL Corporation

29. Mechanical Characteristics
29.1
29.1.1
29.1.2
32059J–12/2010
Thermal Considerations
Thermal Data
Junction Temperature
Table 29-1
Table 29-1.
The average chip-junction temperature, T
where:
• θ
• θ
• θ
• P
• T
From the first equation, the user can derive the estimated lifetime of the chip and decide if a
cooling device is necessary or not. If a cooling device is to be fitted on the chip, the second
equation should be used to compute the resulting average chip-junction temperature T
Symbol
θ
θ
θ
θ
1.
2.
637.
Table 29-1 on page
Consumption” on page
JA
JC
JA
JC
JA
JC
HEAT SINK
A
D
= ambient temperature (°C).
= device power consumption (W) estimated from data provided in the section
= package thermal resistance, Junction-to-ambient (°C/W), provided in
= package thermal resistance, Junction-to-case thermal resistance (°C/W), provided in
T
T
J
J
=
=
T
summarizes the thermal resistance data depending on the package.
= cooling device thermal resistance (°C/W), provided in the device datasheet.
T
A
A
Parameter
Junction-to-ambient thermal resistance
Junction-to-case thermal resistance
Junction-to-ambient thermal resistance
Junction-to-case thermal resistance
+
Thermal Resistance Data
+
P (
(
P
D
D
×
×
θ (
637.
θ
HEATSINK
JA
625.
)
+
θ
JC
) )
J
, in °C can be obtained from the following:
Condition
Still Air
Still Air
Package
TQFP64
TQFP64
TQFP48
TQFP48
AT32UC3B
Table 29-1 on page
49.6
13.5
51.1
13.7
Typ
”Power
J
⋅C/W
⋅C/W
in °C.
Unit
637