What's Cookin'

A wish was to extend MEEPS with a 7-Segment Clock Display which is usable for a clock or a temperature indicator or a counter. For a clock a display is needed with 4 segments for hours and minutes and a colon in between. These 7-segment display's are sold ready made but the LED's are multiplexed so an extra circuit is needed to connect the display. The nicest solution is of course to place the display together with the full multiplexing circuitry on one MEEPS board.

Because it's very handy to tryout a circuit before the PCB goes into production we have to make a prototype first. This is a nice opportunity to discover the power of MEEPS. The circuit itself can be built on a breadboard but this solution is only temporary. There comes a day you need the breadboard for other purposes. On the breadboard on the above picture the whole circuit is built and is working for the full 100%.

MEEPS also has a Protoboard, a prototyping board with a design area of 19x21 solderpads on a 0,1" grid. The picture above shows the same circuitry as on the breadboard, also fully functional. This circuit is much more compact and the need to disassemble the PCB is gone. The design on the MEEPS Protoboard already looks a lot like the final design. It could easily be that this is the final circuit if you only need a couple of PCB's.

Before a MEEPS PCB goes into production there must be a design first for the final PCB. This design look a lot like the design on the MEEPS Protoboard, only the components are placed a little bit different. The display is centered nicely and the placement of the components is optimised a little. Because the design for the 7-Segment Clock Display can be single sided it's easy to etch a prototype of it. On the picture above you can see a sheet with the PCB design together with the very first real prototype. This prototype also works like a charm and the PCB can now go into production.

This is why we did it in the first place... A complete digital clock with a 7-segment display, here in a blue version. From left to right you can see the MEEPS +5V Power Supply, a I2C Real Time Clock based on the DS1307 on a MEEPS Protoboard, a MEEPS ATtiny2313 controller board to control the whole circuitry and the brandnew prototype of the 7-Segment Clock Display board.