ADSP-BF512 Datasheet, PDF (54/62 Pages) Analog Devices – Blackfin Embedded Processor

ADSP-BF512/BF514/BF516/BF518 (F)
THERMAL CHARACTERISTICS
To determine the junction temperature on the application
printed circuit board use:
T_J = T_CASE + (Ψ_JT × P_D)
where:
T_J = Junction temperature (؇C)
T_CASE = Case temperature (؇C) measured by customer at top
center of package.
Ψ_JT = From Table 45
P_D = Power dissipation (see Power Dissipation on Page 51 for
the method to calculate P_D)
Values of θ_JA are provided for package comparison and printed
circuit board design considerations. θ_JA can be used for a first
order approximation of T_J by the equation:
T_J = T_A + (θ_JA × P_D)
where:
T_A = Ambient temperature (؇C)
Values of θ_JC are provided for package comparison and printed
circuit board design considerations when an external heat sink
is required.
Values of θ_JB are provided for package comparison and printed
circuit board design considerations.
In Table 45, airflow measurements comply with JEDEC stan-
dards JESD51-2 and JESD51-6, and the junction-to-board
measurement complies with JESD51-8. The junction-to-case
measurement complies with MIL-STD-883 (Method 1012.1).
All measurements use a 2S2P JEDEC test board.
The LQFP-EP package requires thermal trace squares and ther-
mal vias, to an embedded ground plane, in the PCB. The paddle
must be connected to ground for proper operation to data sheet
specifications. Refer to JEDEC standard JESD51-5 for more
information.
Preliminary Technical Data
Table 44. Thermal Characteristics for SQ-176-2 Package
Parameter
θ_JA
θ_JMA
θ_JMA
θ_JC
Ψ_JT
Ψ_JT
Ψ_JT
Condition
0 Linear m/s Airflow
1 Linear m/s Airflow
2 Linear m/s Airflow
Not Applicable
0 Linear m/s Airflow
1 Linear m/s Airflow
2 Linear m/s Airflow
Typical
TBD
TBD
TBD
TBD
TBD
TBD
TBD
Unit
؇C/W
؇C/W
؇C/W
؇C/W
؇C/W
؇C/W
؇C/W
Table 45. Thermal Characteristics for BC-168-1 Package
Parameter
θ_JA
θ_JMA
θ_JMA
θ_JC
Ψ_JT
Ψ_JT
Ψ_JT
Condition
0 Linear m/s Airflow
1 Linear m/s Airflow
2 Linear m/s Airflow
Not Applicable
0 Linear m/s Airflow
1 Linear m/s Airflow
2 Linear m/s Airflow
Typical
TBD
TBD
TBD
TBD
TBD
TBD
TBD
Unit
؇C/W
؇C/W
؇C/W
؇C/W
؇C/W
؇C/W
؇C/W
Rev. PrE | Page 54 of 62 | March 2009