We have a six layer board. Two layers are dedicated to GND and Power plane
for the entire board. It may be possible to a allocate quite a large copper
area in one of the 2 remaining internal layers to an Analog GND plane for
the switching section. As I imagine this is a 'noisey' GND return that
should be seperate from the Digital plane.
This is to be a hand-held consumer product in a very small case, so large
open space for air flow, or fan ventilation is'nt an option open to us.
thanks for you support
Tim
At 04:08 PM 7/23/98 -0400, Andrew Ingraham wrote:
>Is this high a temperature consistent with how much power you expected
>the pass transistor to dissipate? Is it functioning correctly?
>
>If you were to isolate the ground plane, the area around the transistor
>would get even hotter. Should it be heat-sinked? How is the airflow?
>
>Regards,
>Andy Ingraham
>
>
_____________________________________________________
Tim Parks
Technical Manager
Ferrotec Ltd
Unit T9
Maple Avenue
Stillorgan Industrial Park
Stillorgan Tel: 00-353-1-2952529
Co. Dublin Fax: 00-353-1-2953625
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