CCS/TMS320F280049C: VDD Pins Circuit

Tobias Ofenberger81

Tool/software: Code Composer Studio

Hi e2e community,

when I tie VREGENZ to low I enable the internal LDO and the 1.2V are on the VDD pins. When I divide the VDD caps (minimum 12µF) through the number of VDD pins I'll get a minimum of 3µF cap per pin. Is it necessary to connect all VDD pins? Or is it enough to put a min. 3µF on each pin and don't connect all VDD pins together.

Best regards,

Tobias

over 7 years ago

0 Devin Cottier over 7 years ago

TI__Guru 60865 points

Hi Tobias,

I'll have to consult with the designers to determine if externally unconnected VDD pins is OK. This might take a few days.

The safest thing to do would be to externally connect the VDD pins. This is implied in the case in the data sheet where there are some bulk capacitors in addition to the per-pin capacitors.