EUP7171
PCB Layout Considerations
The EUP7171 regulator is packaged in plastic SOP-8
package. This small footprint package is unable to
convectively dissipate at high current levels. The
junction temperature should be kept well away from
the thermal shutdown temperature in normal
operation. To do this, care should be taken to derate
the part dependent on several variables: the thickness
of copper on PCB; the area of top side copper used
and the airflow. Since multiple GND pins on the
SOP-8 package are internally connected, the lowest
thermal resistance will result if these pins are tightly
connected on larger ground traces and more copper on
top side of the printed circuit board.
If the large ground trace around the IC is unavailable
on top, numerous vias from the ground connection to
the internal ground plane will help. The vias should be
small enough to retain solder when the board is wave-
soldered.
Additional improvements can be achieved with a
constant airflow across the package.
Test Circuit
Figure 2. Load transient (+2A ~ –2A) test circuit
DS7171 Ver1.0 Mar. 2005
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EUTECH [ EUTECH MICROELECTRONICS INC ]
