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Matt Thorn
10-27-2010, 06:47 AM
I wanted to post this in the LED String Blade forum, but for some reason I can't post anything on that forum.

I'm making my first LED string blade, and I'm thinking about using six 7027 BuckToot 350mA constant-current LED drivers for each of the six sections of the blade. I'm putting it in a converted Force FX Vader, and planning to maintain the scrolling effect. (I'll be using the standard battery/speaker pack that comes with the Vader Force FX.)

So my question is this: Is it possible to have positive leads forking out from the VDD on the board to the "VIN +" lines of the BuckToots, and the have "LED +" leads on the other side come together again in the common positive lead of the LED string...? I've made a diagram illustrating what I want to do. Hope it's decipherable.

http://lh5.ggpht.com/_THBqz9vPciU/TMgqOSTvnoI/AAAAAAAAF3g/PidiPht2Er4/s800/LED%20string%20Force%20FX%20diagram.png (http://picasaweb.google.com/lh/photo/MMv7vBGLlNAQdHZaouRnjA?feat=embedwebsite)

Equality 7-2521
10-27-2010, 08:03 AM
According to this sim (http://www.falstad.com/circuit/#%24+1+5.0E-6+0.019691167520419408+10+5.0+50%0Av+272+448+272+3 84+0+0+40.0+3.0+0.0+0.0+0.5%0A162+464+144+400+144+ 1+2.0+1.0+0.0+0.0%0A162+464+112+400+112+1+2.0+1.0+ 0.0+0.0%0As+208+448+272+448+0+1+false%0As+304+448+ 368+448+0+1+false%0A162+464+208+400+208+1+2.0+1.0+ 0.0+0.0%0A162+464+240+400+240+1+2.0+1.0+0.0+0.0%0A v+368+448+368+384+0+0+40.0+3.0+0.0+0.0+0.5%0As+400 +448+464+448+0+1+false%0A162+464+304+400+304+1+2.0 +1.0+0.0+0.0%0A162+464+336+400+336+1+2.0+1.0+0.0+0 .0%0Av+464+448+464+384+0+0+40.0+3.0+0.0+0.0+0.5%0A w+272+384+368+384+0%0Aw+368+384+464+384+0%0Aw+400+ 336+400+448+0%0Aw+464+384+512+384+0%0Aw+512+384+51 2+336+0%0Aw+512+336+464+336+0%0A162+464+80+400+80+ 1+2.0+1.0+0.0+0.0%0A162+464+176+400+176+1+2.0+1.0+ 0.0+0.0%0A162+464+272+400+272+1+2.0+1.0+0.0+0.0%0A w+400+80+208+80+0%0Aw+208+80+208+448+0%0Aw+464+336 +464+304+0%0Aw+464+304+464+272+0%0Aw+464+272+464+2 40+0%0Aw+464+240+464+208+0%0Aw+464+208+464+176+0%0 Aw+464+176+464+144+0%0Aw+464+144+464+112+0%0Aw+464 +112+464+80+0%0Aw+400+80+400+112+0%0Aw+400+112+400 +144+0%0Aw+400+272+400+304+0%0Aw+400+304+400+336+0 %0Aw+400+176+400+208+0%0Aw+400+208+400+240+0%0Aw+4 00+176+304+176+0%0Aw+304+176+304+448+0%0A), it will.

Matt Thorn
10-27-2010, 08:22 AM
According to this sim (http://www.falstad.com/circuit/#%24+1+5.0E-6+0.019691167520419408+10+5.0+50%0Av+272+448+272+3 84+0+0+40.0+3.0+0.0+0.0+0.5%0A162+464+144+400+144+ 1+2.0+1.0+0.0+0.0%0A162+464+112+400+112+1+2.0+1.0+ 0.0+0.0%0As+208+448+272+448+0+1+false%0As+304+448+ 368+448+0+1+false%0A162+464+208+400+208+1+2.0+1.0+ 0.0+0.0%0A162+464+240+400+240+1+2.0+1.0+0.0+0.0%0A v+368+448+368+384+0+0+40.0+3.0+0.0+0.0+0.5%0As+400 +448+464+448+0+1+false%0A162+464+304+400+304+1+2.0 +1.0+0.0+0.0%0A162+464+336+400+336+1+2.0+1.0+0.0+0 .0%0Av+464+448+464+384+0+0+40.0+3.0+0.0+0.0+0.5%0A w+272+384+368+384+0%0Aw+368+384+464+384+0%0Aw+400+ 336+400+448+0%0Aw+464+384+512+384+0%0Aw+512+384+51 2+336+0%0Aw+512+336+464+336+0%0A162+464+80+400+80+ 1+2.0+1.0+0.0+0.0%0A162+464+176+400+176+1+2.0+1.0+ 0.0+0.0%0A162+464+272+400+272+1+2.0+1.0+0.0+0.0%0A w+400+80+208+80+0%0Aw+208+80+208+448+0%0Aw+464+336 +464+304+0%0Aw+464+304+464+272+0%0Aw+464+272+464+2 40+0%0Aw+464+240+464+208+0%0Aw+464+208+464+176+0%0 Aw+464+176+464+144+0%0Aw+464+144+464+112+0%0Aw+464 +112+464+80+0%0Aw+400+80+400+112+0%0Aw+400+112+400 +144+0%0Aw+400+272+400+304+0%0Aw+400+304+400+336+0 %0Aw+400+176+400+208+0%0Aw+400+208+400+240+0%0Aw+4 00+176+304+176+0%0Aw+304+176+304+448+0%0A), it will.
Wow! Thank you! I once downloaded a circuit-simulation program, but I couldn't make heads or tails of it. I will give it a "real world" test tomorrow and let you know how it works. The next question is if I can coax 2100mA out of the Force FX board. Wish me luck.

Equality 7-2521
10-27-2010, 09:22 AM
Here's the schematic import for anyone who wants to download (import) and run the simulation.

---START---
$ 1 5.0E-6 0.019691167520419408 10 5.0 50
v 272 448 272 384 0 0 40.0 3.0 0.0 0.0 0.5
162 464 144 400 144 1 2.0 1.0 0.0 0.0
162 464 112 400 112 1 2.0 1.0 0.0 0.0
s 208 448 272 448 0 1 false
s 304 448 368 448 0 1 false
162 464 208 400 208 1 2.0 1.0 0.0 0.0
162 464 240 400 240 1 2.0 1.0 0.0 0.0
v 368 448 368 384 0 0 40.0 3.0 0.0 0.0 0.5
s 400 448 464 448 0 1 false
162 464 304 400 304 1 2.0 1.0 0.0 0.0
162 464 336 400 336 1 2.0 1.0 0.0 0.0
v 464 448 464 384 0 0 40.0 3.0 0.0 0.0 0.5
w 272 384 368 384 0
w 368 384 464 384 0
w 400 336 400 448 0
w 464 384 512 384 0
w 512 384 512 336 0
w 512 336 464 336 0
162 464 80 400 80 1 2.0 1.0 0.0 0.0
162 464 176 400 176 1 2.0 1.0 0.0 0.0
162 464 272 400 272 1 2.0 1.0 0.0 0.0
w 400 80 208 80 0
w 208 80 208 448 0
w 464 336 464 304 0
w 464 304 464 272 0
w 464 272 464 240 0
w 464 240 464 208 0
w 464 208 464 176 0
w 464 176 464 144 0
w 464 144 464 112 0
w 464 112 464 80 0
w 400 80 400 112 0
w 400 112 400 144 0
w 400 272 400 304 0
w 400 304 400 336 0
w 400 176 400 208 0
w 400 208 400 240 0
w 400 176 304 176 0
w 304 176 304 448 0
---END---

Matt Thorn
10-27-2010, 06:32 PM
:shock: Um... Okay. I have no idea what any of that is, but if it means I can have a common positive on both sides of six LED drivers, that's a good thing.:cool:

Equality 7-2521
10-27-2010, 07:30 PM
Sorry, that wasn't very clear.

The simulator applet that I linked to can be downloaded and run locally, plus it also allows importing/exporting of schematics. The text above is the import data to recreate your schematic.

Sunrider
10-27-2010, 08:42 PM
Ambitious you are. I like it. :)
For more current upgrade pcb transistors?

Matt Thorn
10-27-2010, 11:50 PM
Sorry, that wasn't very clear.

The simulator applet that I linked to can be downloaded and run locally, plus it also allows importing/exporting of schematics. The text above is the import data to recreate your schematic.
Haha. No, you were clear enough. It's just that the data looks like alphabet soup to me. :p And with my current limited understanding of electronics, I doubt I could use the applet anyway. :oops: But thanks all the same.

Matt Thorn
10-27-2010, 11:56 PM
Ambitious you are. I like it. :)
For more current upgrade pcb transistors?
I did think about adding transistors, but it hadn't occurred to me to replace those on the Force FX board with higher gain transistors. Brilliant thinking. That might eliminate the need for the BuckToots entirely. Either way, I'm a bit worried about whether or not the 3-AA battery pack will be sufficient.

Matt Thorn
10-29-2010, 02:01 AM
I'm still unable to post anything on the LED String Blade forum. :(

The Buck Toot drivers produced nothing. Nada. Nary a flicker.

So I tried a "standard" direct connection like the one Eastern introduced here (http://www.fx-sabers.com/forum/index.php?topic=13567.0).

I'm using 66 30mA LEDs, with 11 LEDs per section. The first four sections are fine, but I'm having trouble getting the sections 5 and 6 to light up. I assumed it was a loose connection, and though I do get those sections to flicker faintly when I jiggle the wires, the connections seem solid.

Will the last two sections not light up because the first four are sucking up all the current? :confused:

Strydur
10-29-2010, 07:42 AM
The string blade section should work correctly now.

Matt Thorn
10-29-2010, 08:02 AM
Thank you, Tim!

Jay-gon Jinn
11-02-2010, 05:44 PM
Hey Matt, have you checked the specs on the bucktoot drivers? They are 10mm in diameter and 19mm long, are you going to have room in the hilt for 6 of them? They also have a minimum voltage requirement of 5 volts, so the stock battery pack may be too little to drive them properly.

Matt Thorn
11-02-2010, 06:57 PM
Thanks for the response, Jay-gon. Four bundled together will fit inside the blade holder, the two others can be squeezed in somewhere. But you're right about the voltage. To get the Buck Toots and 66-LED string to work with a Force FX board, I would need a different battery pack, a voltage regulator for the board, and six relays or transistors, so packing all this into a Force FX hilt would require so much modification that it would be easier to start with an empty hilt.

I ended up doing a straightforward 5W LedEngin red conversion so that the guy I did it for would have it in time for a Halloween party where he entertained the children in full Darth Vader costume. He was quite happy with the conversion.

Jay-gon Jinn
11-02-2010, 09:10 PM
Ah, glad you got it going for the guy....I thought it would be a challenge to get all that into an fX hilt, even with their immense size when compared to an MHS.

Matt Thorn
11-02-2010, 09:53 PM
Ah, glad you got it going for the guy....I thought it would be a challenge to get all that into an fX hilt, even with their immense size when compared to an MHS.
Indeed. The direct drive would have worked if I had settled for a smaller number of LEDs. :-? But now that I have this perfectly good LED string, I think I'm going to put it in a 1" blade (this guy wanted a 3/4" blade, but there's no way to hide the edges in such a narrow blade) and do a build from scratch that uses the Buck Toots and a 7.2V li-ion battery pack.

People had been asking (Don't remember if it was here or on fx-sabers) about how to make a really solid plug and socket so you don't pull the guts out of the blade when trying to remove it. For what it's worth, here's how I did it in the 3/4" blade:
http://lh6.ggpht.com/_THBqz9vPciU/TNDn6IjVYoI/AAAAAAAAF3w/1TcQFq4iq60/s800/DSCN0492.JPG (http://picasaweb.google.com/lh/photo/afySzGicbvqJUvMrvYsFGg?feat=embedwebsite)
Wires soldered and held in place with hot glue.
http://lh4.ggpht.com/_THBqz9vPciU/TNDn7G8LZPI/AAAAAAAAF34/ay8MzpoavtM/s800/DSCN0493.JPG (http://picasaweb.google.com/lh/photo/9Cu6GctEIH4-ulZMtZNDIQ?feat=embedwebsite)
The plastic shield wouldn't fit into the blade as is, so I cut off enough of it to make it fit.
http://lh3.ggpht.com/_THBqz9vPciU/TNDn76lHHRI/AAAAAAAAF4A/d_oQS9BRM2M/s800/DSCN0494.JPG (http://picasaweb.google.com/lh/photo/IMGEd4Ah66gpa0wznpeFOg?feat=embedwebsite)
Drill and tap two holes through the blade and the metal case of the plug.
http://lh4.ggpht.com/_THBqz9vPciU/TNDn83fwzxI/AAAAAAAAF4I/GQZuxZMUFsk/s800/DSCN0495.JPG (http://picasaweb.google.com/lh/photo/sFpDYwBKVW96_J_Qs2fxBQ?feat=embedwebsite)

http://lh4.ggpht.com/_THBqz9vPciU/TNDn9jHlVcI/AAAAAAAAF4Q/N_FtrVapWdQ/s800/DSCN0496.JPG (http://picasaweb.google.com/lh/photo/wtrJ_e9dKoNXmIam4JGt4g?feat=embedwebsite)
Screw in two retention screws.
http://lh3.ggpht.com/_THBqz9vPciU/TNDn-tzAgII/AAAAAAAAF4Y/QvJAFT3lPxU/s800/DSCN0497.JPG (http://picasaweb.google.com/lh/photo/Ij0xzy9nzVJ4yj4_sEW98g?feat=embedwebsite)
I used an M4 size screw.
http://lh3.ggpht.com/_THBqz9vPciU/TNDn_uv05NI/AAAAAAAAF4k/PScE6_6CvAc/s800/DSCN0498.JPG (http://picasaweb.google.com/lh/photo/ScnUxBNcuHv6Fpc7QKSTAg?feat=embedwebsite)
I clipped the flanges of the socket, so that it would fit into the 1" IO blade holder, and fixed the socket in place with J-B Weld and hot glue.

This setup is really solid: easy to plug in and remove.

Skottsaber
11-03-2010, 10:21 AM
Nice setup with the blade, Matt!

I take it your screw didn't go all the way through? Because it would go through the connector?

Just for general info, the Parks Phase blades have a screw running through the entire blade, but it goes through the PCB, like so:

http://dl.dropbox.com/u/1237687/TCSS%20Posts/Luke%20ROTJ/SANY0070_783x588.jpg

Matt Thorn
11-03-2010, 04:49 PM
Nice setup with the blade, Matt!

I take it your screw didn't go all the way through? Because it would go through the connector?
Correct. There are two short screws on each side.

Just for general info, the Parks Phase blades have a screw running through the entire blade, but it goes through the PCB, like so:

Whoa! First time I ever saw the electronics of a phase blade. I had no idea the driver was built right into the blade. Slick stuff. Makes the HyperBlade seem primitive in contrast. Thanks for that photo.