Board design and implementation for 8-bit avr microcontrollers in an educational environment

Abstract

This paper is presenting the design process and implementation for a microcontroller board to be used in HAMK's embedded system design course. The microprocessor on the board is an 8-bit AVR ATMega32U4. This controller is capable of driving and reading several onboard peripherals, such as: LED's, an external display, temperature sensor, additional memory, buttons, IR transmitter and IR receiver. The board features an external high voltage power input for use in PLC cabinets. Programming is done with ATMEL Studio without the need for a special programmer. A development board is realised, meeting the basic requirements. Buttons can be read, LED's can be driven. Communication can be instantiated with the I²C components. The external display is controlled over a dedicated header. The power supply has proven to handle voltages up to 40 V and output 3 A at 5 V. Shorting the supply can be done up to forty seconds before reaching the regulators thermal limits. All components are housed on a custom PCB. Most components are in SMD format external connections. Cost is lowering when larger quantities are ordered; A single unit costs €87,62, ten units €21,46 and the price for one hundred units drops to €15,98.