Power AVR microcontroller with AA battery compactly

Are they tired of using huge batteries in embedded design? The guy from Spritesmod managed to power the AVR microcontroller from a single AA battery with simple circuitry driven by the AVR microcontroller itself. As industrial devices use DC-DC converters to rise voltages from 1.5V to 5V, there is the same principle used as well, AVR MCU itself does just DC-DC converter control.   He didn’t use a dedicated PWM control chip but managed to drive converter with PWM generated with Attiny13, occupying a one-timer for this. Of course, it has to start before MCU can create a control signal. For this, a starter button is used, which raises voltage for a short time to be suitable when pushed. Then microcontroller starts and continues powering itself. With the MOSFET switch efficiency of the circuit reaches up to 73 percent. The main advantages of such a powering method are low part count and soft power off. But on the other hand, efficiency is still relatively low, and there is a timer and one MCU pin occupied. Continue reading

Cornell University AVR student projects

At the end of the academic year, ECE476 Cornell University students produced about 40 new projects primarily based on Atmega32 every year, and students have the responsibility to choose their final project. So there, you can find various exciting ideas and designs, including video games, robots, MIDI synthesizers, clocks, speech recognition, and so on.   Projects here are accumulated since 1999 Spring(over 200 older projects). So you can surf inside pretty big knowledge base and find ideas, solutions and inspiration for your own designs.   Continue reading