YO3BN - Atmega AVR Development Board v1

AVR ATmega Development Board v1

Posted at - 16th December 2017

Simple Atmega1284-PU / Atmega32-PU development board. It helps with the firmware development and new projects prototyping thanks to the following features:

Easy connectivity design
16MHz Quartz
Onboard RESET button
5V regulator
Filtered power supply
Filtered power supply for AVCC (ADC module)
Auxiliary outputs for power supply
All of 32 GPIO pins available

Other potential improvements:

Power supply presence by LED indicator
Switching power supply instead 7805 in order to increase power efficiency (and noise ;) )
Coaxial jack for power supply input
Lowering the value of 2k2 resistor from RESET line
ZIF socket
Reverse polarity protection diode
Fuse + fuse socket

The schematic

Construction Details

Because I'm in a hurry most of the time I did'n draw this into *CAD programs, maybe I'll do for version two.

Other Notes

Fuse bits of MCU should be modified in order to use external crystal
The current consumption is about 32mA with 16MHz crystal oscillator set to full swing, CPU in while loop, JTAG disabled and no loads to any pin

Updates:

The RESET button it is hard to press because it is placed near a big cap, so it should moved in next designs.
The capacitor at ADC-REF pin was changed to a lower value - 100nF. That's because it is a high impedant voltage supply and a big caps. charge slowly.

73 de YO3BN