doimant / kicad-atmega-board

ATMega Barebone PCB. Applicable for battery powered applications. Usable microcontrollers: ATTiny88, ATmega48A/PA, 88A/PA, 168A/PA, 328/P

ATMega Board

The usual Arduino boards like the Arduino Uno , Nano, Mini etc. are only conditionally suitable for battery operation.

The current requirement of the built-in LEDs, the USB-UART interface and the quite high quiescent current of the LDO regulator is too high for a longer operation on a battery, even if the microcontroller is in sleep mode.

On the ATMega board only the most necessary components are installed, which are necessary for the operation of a microcontroller. This makes it possible to operate the controller with batteries for a longer time. The screw terminals allow stable and trouble-free connections with external components.

With the help of a jumper the power indicator LED (consumes about 3mA) can be switched on or off as needed.

Limitations compared to the usual Arduino boards

• Programming must be done via the ISP adapter.
• For serial communication an external FTDI adapter is required.
• The analog ports A6 and A7 (e.g. compared to an Arduino Nano) are not available.
• No 3.3V output. But you can use the whole board instead of a 5V LDO with a 3.3V LDO (MCP-1703-3302MB or HT7833-1).

Other technical data

• Usable microcontrollers: ATTiny88, ATmega48A/PA, 88A/PA, 168A/PA, 328/P
• The crystal is exchangeable (depending on the inserted microcontroller max. 20Mhz)
• Supply voltage via JST XH connector or VIN-Pin min. 6V, max. 15V
• Max. 200mA current load (the LDO has a limit of 250mA, the AVR controllers 200mA.)
• Power consumption with an ATMega328P in sleep mode "SLEEP_MODE_PWR_DOWN" and disabled ADC < 10µA

Circuit diagram as PDF file

Sheet

The PCB