What does the -PU, 16PU means ?

Hey guys, I have a very simple question here :

I saw that in Atmega 8, stated there is like Atmega8-16PU, and for Atmega 328 is like Atmega 328-PU, so what does the PU means actually ?

Thank you

It's the package. PU stays for a DIP chip.

They come in different flavors:
-AU: 32-lead, TQFP
-MMH: 28-pad QFN/MLF
-MU: 32-pad QFN/MLF
-PU: 28-lead PDIP

Keep in mind that a 328-PU is slightly different than a 328P-PU with the latter being a picoPower device. For more info on the picoPower aspect of Atmel chips, refer to the web site: http://www.atmel.com/technologies/lowpower/default.aspx

So what is the difference between At mega 8A-PU and At mega 8-16PU??

Thank you

They are pretty much the same.

ATmega8-16-PU means it's the 16MHz PDIP version of the ATmega8 (It's also available in an 8 MHz version)
The ATmega8A is only available in 16MHz version, therefore they usually don't add the 16 suffix to the name.

ATmega8A is an improved version of ATmega8 with better power characteristics. It is compatible with ATmega8.

How do you know about that ? Any standard for the prefix naming ?

I haven't seen a naming standard but the naming convention can be figured out from the two pages I linked to.

How do you know about that ?

It is all spelled out in the datasheet.

Vincent19:
How do you know about that ? Any standard for the prefix naming ?

Maybe you could . . . look on the Atmel website, read some datasheets.