I found a packet of 10 micro-controller in my brother's electronics stuff. It reads "Atmel ATMEGA168A-PU".

I looked at Atmel's website but could not find any such product. I need it's data sheet to know that it is capable of ? I would like to play with it.

  • 3
    \$\begingroup\$ If you search on Google for ATMEGA168A-PU you get the datasheet as the first result. This doesn't deserve to be a question on this site. \$\endgroup\$
    – m.Alin
    Dec 2, 2012 at 2:29
  • \$\begingroup\$ As an aside, the letters Atmel uses as suffixes denote the microcontroller version (A) and its packaging (PU). On page 529 of the datasheet Anindo linked, you'll find Ordering Information which shows the various ATMEGA168's available. The "P" means it uses package 28P3. The datasheet explains this package on page 537, and it's a through-hole Plastic Dual Inline Package (PDIP). The "U" means it is lead-free. ref \$\endgroup\$
    – JYelton
    Dec 2, 2012 at 2:32

2 Answers 2


Here you go. Datasheet for the ATmega48A; ATmega48PA; ATmega88A; ATmega88PA; ATmega168A; ATmega168PA; ATmega328; ATmega328P - Atmel 8-bit Microcontroller with 4/8/16/32KBytes InSystem Programmable Flash

This microcontroller can be used to make your home-grown Arduino clone, among other things. The DIP part lends itself to making the Really Bare Bones Board quite well.


To add a bit more to what Anindo Ghosh said:

Atmel uses the following layout to their labels: PrefixDeviceOption-Suffix (there are no spaces so this is hard to read, with spaces it would look like: Prefix Device Option-Suffix)

enter image description here

The AT means it is an Atmel part, followed by the option (this may be missing in some devices.) Then a hyphen separates the speed and package type (and sometimes temperature range and processing.)

So for the part number you gave, ATMega168A-PU:

  • AT means Atmel
  • Mega168 is the part number
  • A is the option, in this case smaller die and lower power usage
  • PU is a DIP package

For more information take a look at Explanation of Atmel’s Part Number Code

So as a rule of thumb, the letter before the dash (-) means:

  • P "Picopower" low-power parts
  • A Newer Fabrication process, lower voltage, lower power, non-Atmel fabricated parts with possibly more noise on A/D inputs
  • V Low-voltage, lower clock frequency parts before "A" came along
  • and nothing is the default part

Also, note that the P and A are not mutually exclusive, meaning that ATMega168PA-PU is a valid part number.


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