I am building a custom low-power Arduino board using a SMD ATmega328 and as few components as possible. I have drawn a schematic and want to get some opinions on whether this design looks good. [image] I have used the Gammon website as my base, however I am trying to use a SMD chip rather than a…

You will need to add the Boot loader to the controller chip before you can use the FTDI. Nicks site shows how to burn the bootloader using the SPI (ICSP) pins. Your circuit looks okay, make sure the crystal is close to the controller pins it connects to, do not run traces in between the crystal le…

[image] LarryD: You will need to add the Boot loader to the controller chip before you can use the FTDI. Yes. I'm going to follow the Gammon site for that! :wink: [image] LarryD: Suggest you add a 6 pin ICSP header to the board, at least the possibility of solder one if need be. Is th…

[image] LarryD: Suggest you just use an Arduino Pro Mini, they have all you need on the board. I need a few more custom capabilities than the pro mini - plus I want the charge circuit and boost circuit on the same PCB

Suggest you use ready built modules (daughter cards) on a Mother board that you design. [image]

Since you sound like this might become a hobby for you, go through this thread, it has ~ 1000 posts of ideas that might tweak some ideas. [image] Share tips you have come across General Electronics This post will contain the index for this thread. This is goin…

Here is an example of a Mother Board design with a Boost Converter, Pro Min and the capability of an DS3231 RTC. [BoxF] [image] From post [image] Share tips you have come across General Electronics [BoxA.jpg] [BoxB.jpg] [BoxC.jpg] [BoxD.jpg] [BoxG.jpg] [BoxH…

Here is my schematic of a one-board 5v boost, battery, and MCU: [image] And here is the PCB. Back: [MCUB] Front: [MCUF]

Three things. Unless you have above average soldering skills, a project using a TQFP form factor is not for you. Making your own SMPS can be quite difficult, you need to use the recommended components (avoid substitutions) all recommended component placement is a necessity. ready made board…

This is the foil pattern for your LM2621. [image]

[image] LarryD: Unless you have above average soldering skills, a project using a TQFP form factor is not for you. This isn't an issue as the company who is making the PCB offers a cheap guaranteed assembly service which I will be using. [image] LarryD: Making your own SMPS can be quite …

Custom MCU using a SMD ATMEGA328

Projects General Guidance

LarryD August 29, 2022, 5:49am 7

Here is an example of a Mother Board design with a Boost Converter, Pro Min and the capability of an DS3231 RTC.

From post

Topic		Replies	Views
Will this work? Atmega1284p Schematic Hardware Development	230	1944	May 19, 2026
PCB con Atmega328 che non funziona Hardware	35	308	October 7, 2026
Moving from arduino prototype to schematics and PCB General Guidance	19	297	June 26, 2026
Bare ATMega328P schematic: Request for Comment Hardware Development	102	2285	August 22, 2025
ATMEGA328P footprint and further development General Electronics	94	2625	August 30, 2024

Custom MCU using a SMD ATMEGA328

Related topics