I tried the tqfp44 footprint that is inside fritzing already, but the associated component DSPIC30F4011 had some missed pins, so i can’t use it. Anybody can help me with a full tqfp44 footprint? many thanks
It wouldn’t have worked anyway. That footprint is a larger pitch than the Atmega1284. Here is a part that should do
Atmega1284.fzpz (10.6 KB)
As always before ordering boards print the pcb footprint out at 1:1 scale and compare it to a real part to make sure it is correct. In addition the recommended thermal pad is present, but Fritzing can’t do the vias that are called for in a SMD part so you need to drag a pad the same size as the thermal pad in to the bottom layer of the sketch and position it on the bottom of the thermal pad in the part. Then drag a hole in to your sketch, place it over the circles in silkscreen and set the via size to 0.2mm. That will connect the top thermal pad in the part with the one you added on the bottom.
Also default DRC won’t pass and the connection to the thermal pad needs to be on the bottom layer as there isn’t enough clearance to pass DRC if it is on the top.
Peter