Purchase microcontroller circuit

[seanyiya]

Does any know where I can purchased already made this ciurcit board and also have like speedo controller??
I've tried making it  myself, but it's just too much trouble..

[justDIY]

if you just want this effect, and only need 8-10 leds



there are simpler ways to achieve it without a microcontroller, namely a 555 timer and a bargraph driver (series number escapes me).   the circuit you posted (there is a latter version with speed / function buttons) allows multiple effects to be programmed into the microcontroller.  it's also expandable to run many many many leds.  oh, to help keep the parts count down, if you're just running standard 5mm leds, the darlington array (IC3 with all the IN/OUT pins) can be eliminated.  you really only need it for leds demanding over 50mA.

Come to think of it - I will be running a few panels in the next week or two for another project.   I can make some of these for you if you're interested.   You'll be on your own as far as assembly and programming, all I can provide is the bare printed circuit board.

[justDIY]

how do you feel about all surface mount parts?

[justDIY]

or if you want to try fabricate your own board - here's my first draft artwork:

schematic:


layout (click for 600dpi version):


the project has changed a bit, I've eliminated the darlington arrays to keep the layout simpler, and also substituted a full 7805 for the 78L05.   Depending on the input voltage, it should give 100ma+ of current without needing a heatsink.  The leds should be wired as a common anode or common cathode array, and I've provided pads for both +5v and 0v.   The 74HC595 can source up to 35mA per output, and sink up to 70mA.

[seanyiya]

if you just want this effect, and only need 8-10 leds



there are simpler ways to achieve it without a microcontroller, namely a 555 timer and a bargraph driver (series number escapes me).   the circuit you posted (there is a latter version with speed / function buttons) allows multiple effects to be programmed into the microcontroller.  it's also expandable to run many many many leds.  oh, to help keep the parts count down, if you're just running standard 5mm leds, the darlington array (IC3 with all the IN/OUT pins) can be eliminated.  you really only need it for leds demanding over 50mA.

Come to think of it - I will be running a few panels in the next week or two for another project.   I can make some of these for you if you're interested.   You'll be on your own as far as assembly and programming, all I can provide is the bare printed circuit board.

how do you feel about all surface mount parts?

Putting together is no problem  putting together bare printed circuit board....
I've never made my own printed circuit board.....
Well... having the flexibility of 8-16 LED would be nice....

[BVnursery]

LM3916 - Dot/Bar Display Driver

[justDIY]

yea thats the sucker!

555 to generate a sawtooth or ramp wave, and the lm3916 to light up the bargraph as the voltage increases (from saw/ramp wave)