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[on:]

Hello there!
Total noob here(I bet you hear that alot  :-)  )
I'm trying to get some basic ideas on how to interface with a flip dot.
I saw some topics on this forum already, but unless I'm mistaken, they deal with matrixes of the things.
I managed to get some single unit ones(from AlfaZeta) and want to start by just interfacing with one.

I'm a total noob in electronics.   However, so far I hear that you can't drive a flip-dot from an arduino pin(due to current restrictions).  So I decided to go with an H-Bridge as it can provide more current and allow me to switch polarity.
Is this a good approach?

I laid out a wiring diagram and was wondering if anyone can tell me if I'm heading in the right direction, or that of a fiery arduino death. :-)



btw...the "motor" is going to be the flipdot...for power, I'm thinking of using a 12v adapter or 9v battery fed via the power jack on the arduino.

Thanks in advance for the help!

[Reply #1 on:]

In regards to flip dot operation, yes, need a pulse of current in either direction to flip it back & forth.

As to your connections: Hard to tell without and finding a spec for the chip & see what you have hooked up.
Fritzing sucks in that regards.
Any chance you can post a real schematic?

[Reply #2 on:]

Thanks for the quick reply!
Sorry for the layout...I'm a noob in that regard as well :-)  Just found out about Fritzing actually...didn't know what else to use(heard of Eagle though).
Anyways...here is the schematic....



In terms of flip dot opertation...their papers say I need a 1ms of 350mA of a minimum of 7.5v

Once again...thanx for the help!

[Reply #3 on:]

For 1mS at 350mA, you're likely to need a large capacitor to supply the current.
9V batteries have a relatively high internal impedance, and it's likely that the voltage during the current pulse is sagging rather a lot.

For best results while experimenting, a bench power supply capable of 1-2A would be good, a second battery for the flipdot would work as well.  You might use AA cells in a holder for that one, and then the voltage sags would be smaller, and not cause processor resets or other weird behavior.

[Reply #4 on:]

Thanks dbvanhorn.

I'll have to look into both alternatives there.
With the capacitor method...I would attach this between the Vcc and Ground, correct?  Would a 200uF(25v) be sufficient you think?

[Reply #5 on:]

Also...other than the above...this h-bridge is a go?

[Reply #6 on:]

I'd say yes, just control  a burst of current one direction or the other, its supposed to stay in place once moved.

[Reply #7 on:]

Roger that!  Thanks for the help guys....I'll wire it up tomorrow possibly.

[Reply #8 on:]

Well...it wasn't "tomorrow" but I eventually got it.
A simple blinker.  At first, I thought I didn't have enough power via usb...but it worked after all!


Makes a nice clicking noise as it flips....and best of all....no smoke, fire, or burning!

I'll upload a video soon...

[Reply #9 on:]

Don't know if this is a permalink.  Let me know if its not working.

https://fbcdn-video-a.akamaihd.net/cfs-ak-ash4/452373/287/10150641562750794_43903.mp4?oh=035080510bfb59c6d22e76c9aecb3331&oe=4F7D2A00&__gda__=1333602816_137b8879fa9bb21a4d9f2937d10af409

[Reply #10 on:]

Playback on the video is terrible.
Please resize pics when you post to 800x600 kind of size, vs 3200 x 1800.

[Reply #11 on:]

Jeez....youre right...sorry about the giant pic....
Video plays ok here and on mobile too....should have uploaded to youtube or something...  sorry again :-)

EDIT: Pic resized!

[Reply #12 on:]

Here is a youtube version of the vid:

[Reply #13 on:]

Looks good!