L6226PDTR Datasheet, PDF (23/31 Pages) STMicroelectronics – DMOS dual full bridge driver

L6226
7
Thermal management
Thermal management
In most applications the power dissipation in the IC is the main factor that sets the maximum
current that can be deliver by the device in a safe operating condition. Therefore, it has to be
taken into account very carefully. Besides the available space on the PCB, the right package
should be chosen considering the power dissipation. Heat sinking can be achieved using
copper on the PCB with proper area and thickness. Figure 21, 22 and 23 show the junction-
to-ambient thermal resistance values for the PowerSO36, PowerDIP24 and SO24 packages.
For instance, using a PowerSO package with copper slug soldered on a 1.5 mm copper
thickness FR4 board with 6cm2 dissipating footprint (copper thickness of 35µm), the R_thJA is
about 35°C/W. Figure 20 shows mounting methods for this package. Using a multi-layer
board with vias to a ground plane, thermal impedance can be reduced down to 15°C/W.
Figure 20. Mounting the PowerSO package
6OXJVROGHUHG
WR3&%ZLWK
GLVVLSDWLQJDUHD
6OXJVROGHUHG
WR3&%ZLWK
GLVVLSDWLQJDUHD
SOXVJURXQG OD\HU
6OXJVROGHUHGWR3&%ZLWK
GLVVLSDWLQJ DUHDSOXVJURXQGOD\HU
FRQWDFWHGWKURXJKYLD KROHV
Figure 21. PowerSO36 junction-amb. thermal resistance vs on-board copper area
ž& :



: LWKR XW* URX QG /D \HU

: LWK *UR XQ G /D \HU
: LWK *UR XQ G /D \HU  YLD

+ R OH V
2Q%RDUG&RSSHU$UHD


              
V T F P
Doc ID 9452 Rev 4
23/31