View Full Version : Best way to connect LEDs to LED64?
JBaymore
05-18-2005, 04:58 AM
I am getting ready to hook up my LED64 card. I am wondering if anyone has some "tried and true" suggestions for setting up the card for connecting all those LEDs to it.
I DON'T want to solder everything directly to the pcb........ inelegant and a pain in the butt. It seems to me that there should be a way to solder a "breakout" connector board or something to it....... ala' the breakout for the Hagstrom KE72 card....... where you have screw terminals for the leads and the breakout plugs into the main card. I don't mind soldering the breakout direct to the LED64...... but don't want to hook the LEDs up direct.
SO...... suggestions and parts sources anyone?
best,
..............john
PS: Phidgets-folk....... here is another minor accessory product for you to sell..... a "breakout card" for the LED64. ;) Or just add connectors right onto the LED64 board somehow.
imported_737nut
05-18-2005, 07:25 AM
You only need one common (-) connection per row so that simplifies things a bit. That means you don't need to run 2 wires for each led. You could probably adapt the Hagstrom 36pin breakout the same way. Hard wire from LED64 to the Hagstrom Break-outs. From that via ribbon cable to the leds.
What i used was Cat5 cable, it allows me 7 leds and and the 8th wire is gnd. Works out quite nicely. You could add a seperate board with a connector at each pnl also.
Rob
JBaymore
05-18-2005, 08:23 AM
737NUT,
Thanks for the reply. Not sure if Hagstrom will sell the breakout uints other than with their cards. SInce a KE72 takes two breakouts....... not sure what they'd do if you ordered a couple extra ;) .
Great idea on the Cat5 stuff for wire.
Are you SURE about the common ground on each row? (I haven't looked at the traces on the pcb yet.) I seem to remember seeing somewhere here a reply from Phidgets that said that is NOT a good practice.
But I couild be wrong about that.
best,
..............john
imported_737nut
05-19-2005, 07:33 PM
All the grounds are common connected. That was verified with my Fluke Meter. I'm driving 50 leds so far with no issues at all! :D The cat 5 does clean up the wiring and makes it allot easier to track.
Rob
phidgets
06-05-2005, 06:29 PM
--From Chester, the developer of Phidgets--
There is no common ground on the LED64, at least from the perspective of the LEDs. There are 32 cathodes, and 2 anodes. It is possible to drive the 64 LEDs with 34 wires, but this would be complex. Much simpler to use 128 wires.
If you do hook the cathodes up to the common ground for the LED64, the LEDs will die very quickly, as up to 3 amps @ 3.3V will be dumped through.
Common cathodes are shared between pairs of LEDs - the pairing goes like
(0,8) (1,9) (32,40) (55,63) etc. So, there are a total of 32 Common
Cathode pairs.
There are two Common Anodes; one has 0-7,16-23,32-39,48-55
The other has 8-15,24-31,40-47,56-63.
------------------------------
BTW- A new version of the LED 64 is being developed which will have 4-pin wire connectors on the board. However, I have NO ETA on this board. Best not to wait on it if you have a project underway.
Thanks
Matt
Hi, jumping in on the leds, how about connecting anunciators with dual leds, must each led be connected seperately and then assign the identical function or is there a way that they both can be connected on the same ledout ?
I added a picturen of the anunciator with dual led.
Thanks for any sugestions.
Marnix
alandyer
06-08-2005, 04:36 AM
I was wondering same thing.
Have those same FDS annunciators.
alandyer
06-08-2005, 04:39 AM
Marnix,
From what I have seen with other sims and my own experimenting, a single LED can give good results.
Regards,
Alan.
JBaymore
06-08-2005, 04:46 AM
This is exactly why I asked a question in another theread about running two LEDs in parallel on the same output.
One thing I have found in testing out the annunciators is that if you are going to illuminate them via a single LED on one side.......... say for a red and a green one in a landing gear status indicator.......
take the LED and a small file (8") and file the tip of the domed plastic "lens" of the LED down flat. Then take some 220 grit silicon carbide sandpaper and lightly "frost" the filed surface and the sides of the lens.
This gives a far more diffuse light to the LED... and more smoothly and "gently" illuminates the engraved legend on the front. The "normal" LED lens is designed to focus the energy in more of a tight "beam"....... which makes the Flight Deck Solutions annunciators illuminate bright on one side and dim on the other.
Even when using a pair of LEDs to light it up I do this. Looks much better.
And as always....... your mileage may vary, not available in all locations, see store for details, and wear sunscreen. :)
best,
......................john
imported_737nut
06-08-2005, 08:23 AM
I tried 2 leds on one output from the led64. WAY to dim :( I run one common ground per row and have had NO problems with over 150 hours of sim time since install of LED64.
Rob
alandyer
06-09-2005, 05:07 AM
Million dollar question:
Did Rob just get lucky with his LED64 ?
For those wondering, I would go with advice from the designer of Phidgets.
(Prof. Fitchett).
imported_Bill
06-15-2005, 06:27 AM
Hi.
This may seem a simplistic question to those who are ahead of me, but, being more enthusiastic for my project rather than skilled, can I ask how to mount the soldered LED's accurately behind the overhead?
Should I build a light frame of some kind to hold the LED's in position. Any other solution would be very welcome.
Best Regards,
Bill
imported_Bill
06-17-2005, 12:33 AM
First, apologies for attempting to 'twist' the thread!
Second, please ignore my above request - brain was in disengaged mode, didn't realise 'my' lights were not on :o !
What I was attempting to talk about is a 737 overhead panel I got from an East European site.
Close examination of the reverse side revealed small (not at first obvious) indentations in which LED's are located.
So I'll now start marrying my Phidgets with it !
Regards,
Bill
OK, thanks guy's, I'll go for the single led option.
John, I am not sure wat kind of led you are referring to, would you have a typnumber or something ?
Marnix