ATmega328: The Brain of Arduino Nano

Earlier I had referred to ATmega328 as the ‘Heart of Arduino Nano’. On second thought I think I have to call it the ‘Brain of Arduino Nano’ which would be a more apt comparison! The processor inside Arduino Nano is Atmel Mega 328, which is usually known as ATmega328. As I have mentioned earlier, it is not easy to see the name inscribed on the processor. I have taken this zoomed image after shining a spotlight over it to see the inscription clearly.

Actual size of ATmega328 is much smaller and it is difficult to see the label so that I have written it over the image! Even this is an enlarged image to fit the size of the slide. Only difference is that the spotlight has not been shined on it. On the Arduino Nano, it is located near the ‘NANO’ label.

Here you can see the location of ATmega328 on the Arduino Nano board. The label has been added by me to make the chip identifiable easily. Even this is a magnified image.

It is an 8-bit AVR RISC based microcontroller which has 32 KB ISP flash memory. AVR is a family of microcontrollers developed by Atmel. RISC stands for reduced instruction set computer, designed to simplify individual instructions given to the computer. This is in comparison with CISC or complex instruction set computer. RISC computer may need more instructions to accomplish a task because the individual instructions are written in simpler code. ISP in this context stands for in-system programming which allows the device to be programmed while installed in the system. This allows easier delivery of firmware updates without the need for specialist programming circuitry on the board. ATmega328 has a maximum CPU speed of 20 MHz.