I wanted a simple project to finish off the summer. Thus my flip clock was born. 

Here we have the star of the build a 7 segment flip display. It works in the same way that flip dots do. A current though the coil will produce a magnetic field that will flip the digit. You have to be careful a pulse too long can burn the coils out.

I'm using an AVR ATMega 48A for the micro controller. It's very similar to the 328p used on the Arduino. There's a basic circuit for driving the buzzer and LED's for the day light alarm. The real time clock chip is a very accurate variant, DS3231. All the switches are connected to a I2C GPIO expander. Nothing special going on here. I plan to use USB to power it. The power filtering is nothing special. 

This is the real star of the show, the driving circuits for the display. The section on the bottom supply's 12v and selects the segment. The upper portion allows you to select the direction and the segment to flip. This was more complex than I first expected. It might be difficult to fit this on the board...

Next I want to work on the PCB and start the mechanical portion. There will be a lot of effort going into the form. I want this to look elegant and professional if I can.  Tune in next week for the next installment of CAN WE BUILD IT?