What are the base connections you need to controll a 328p outside of an arduino?

Hi there! I am working on a project that's smaller than the arduino pro mini. That's why i need the 328p on a pcb. I am working on a schematic, and I need to know; What are the components/connections I need to make to let it function like a simple arduino? I don't need voltage regulators or led's from the board. Thanks!

Do a Google search for "barebones Arduino" and you will get over 300,000 hits

Or look up Nick Gammon.

Adding a battery is sufficient in many cases.

I have built my '328 projects based on this Arduino to Breadboard tutorial

...R

CasperdHaan:
Hi there! I am working on a project that's smaller than the arduino pro mini. That's why i need the 328p on a pcb. I am working on a schematic, and I need to know; What are the components/connections I need to make to let it function like a simple arduino? I don't need voltage regulators or led's from the board. Thanks!

Clearly what 'connections' you need depends entirely on the project .......................

As to what components you can ommit, from for example an Arduino Pro Mini schematic, depends on what the project actually does ............

Perhaps explain what the project actually is ?

srnet:
Perhaps explain what the project actually is ?

It's a digital watch that works on a lipo battery. It uses i2c for a oled display, and for the clock part I use a ds1302. It can read the battery voltage on A3 through a voltage divider and has a button on D9.

CasperdHaan:
It's a digital watch that works on a lipo battery. It uses i2c for a oled display, and for the clock part I use a ds1302. It can read the battery voltage on A3 through a voltage divider and has a button on D9.

You should be able to implement that with one of the Attiny MCUs. They are a lot smaller than the Atmega 328.

...R

Whitch one? I need at least 20Kb of flash memory for my program and the libary for the display. I need 1 analog input, I2C support and 5 I/O's.

CasperdHaan:
Whitch one? I need at least 20Kb of flash memory for my program and the libary for the display. I need 1 analog input, I2C support and 5 I/O's.

Slowly, the details are being revealed ..........................................

Are you using the 4x4mm UFBGA package? The 4x4mm VQFN package? Something bigger?