I believe the top picture is the 328P-AU, 32-pin TQFP package,
https://www.digikey.com/product-detail/en/microchip-technology/ATMEGA328P-AU/ATMEGA328P-AU-ND/1832260
while the bottom is the 328P-MU, a 32 pin leadless package.
https://www.digikey.com/product-detail/en/microchip-technology/ATMEGA328P-MU/ATMEGA328P-MU-ND/1914588
or this one if it's not 328P, just 328:
https://www.digikey.com/product-detail/en/microchip-technology/ATMEGA328-MU/ATMEGA328-MU-ND/2271028