Arduino nano standalone - pcb to be manufactured

Question

Using EasyEDA I've designed a standalone Arduino nano and plan to have a small PCB manufactured by jlcpcb. I've used the Nano's user manual as a reference for the PCB; within this scope I've used the same microcontroller (ATMEGA168-20AU) and kept close to the original design.

The circuit is modestly basic and will use a blank target ATMEGA168 placed by jlcpcb - my question is - From a programmer Arduino, do I flash the bootloader and program the target micro through the ICSP (left hand side) or is something else required for bootloader plus program? Is the circuit schematic sufficient to work? (could be opening a can of worms here in asking that)

Thanks

ATMEGA168-20AU

• Gil: I do not see any high frequency bypass capacitors.
• AJ_Smoothie: Add the capacitors suggested in the answer (you can look to the manual for reference), and as good practice, add a pin header with several extra pins on it. This has saved my butt countless times. They won't take up much space at all and you never know when they might come in handy, even just for testing.

Answer 1

You program the chip through ICSP, yes. Whether or not you include a bootloader is optional - you don't need a bootloader to program through ICSP, that is only for if you want to program through the UART pins and a USB to UART adapter.

Your circuit doesn't appear to include any "bypass" capacitors. These are small capacitors (usually 100nF) placed close to each power (VCC) pin on all chips. These are not optional and are required for the proper running of the chip.