I haven't tried to measure the current across the LED, but judging from the brightness I'd say it's getting enough. The LED negative contacts on the board seem to pretty much provide a straight path to ground when active allowing the MOSFET gate to fully desaturate. I'm not sure how much power the board itself actually draws either, but I'm driving it with a 5V/1A regulator.Originally Posted by Dethlore
I'm driving my board with a 5V reg as well. I think my problem though is that I'm using N type fets and have to get gate voltage higher than the drain to fully saturate. My setup is a bit silly though for a first attempt at saber building.
With a 7.2V 18650 pack, powering the LM3914 volt meter, 555 timer (to pulse a 670nm Rebel), the LM1185 volt regulator which powers the board, and 3 670nm Rebels (one pulsed by the 555). Getting everything to work JUST right has been a fun difficulty.
Sounds like you like your saber building to be a bit of an adventure. I can relate to that, good for you. My first serious build was with an Arduino Nano and 3 N-channel FETs to control color-change. (http://forums.thecustomsabershop.com...6-Novus-Animus)I'm driving my board with a 5V reg as well. I think my problem though is that I'm using N type fets and have to get gate voltage higher than the drain to fully saturate. My setup is a bit silly though for a first attempt at saber building.
With a 7.2V 18650 pack, powering the LM3914 volt meter, 555 timer (to pulse a 670nm Rebel), the LM1185 volt regulator which powers the board, and 3 670nm Rebels (one pulsed by the 555). Getting everything to work JUST right has been a fun difficulty.
I'm not sure how your setup is wired or what your experience level is, but if you switch to P-channel MOSFETs then you just have to ensure the gates are pulled to ground and don't have to worry about driving the gate pin to a high enough voltage. Also, if you move your N-channel FETs to the negative side of your LED then you don't have to drive the gate as high to get it to fully saturate and turn all the way "on". You should just have to drive it at whatever the Vgs spec says on the datasheet for your MOSFET.
As far as experience goes, I'm really just a beginner that loves playing with it. I've built a few laser drivers and a few basic circuits for nightlights and fan controllers and such... This is probably the most complex thing I've done. I'd LOVE to get my hands on a nano and play around with that! Here's the latest drawing of my circuit.. it has changed slightly, but for the most part... it gives the general idea...
and yes, I do know that I drew the mosfet symbols wrong. haha
This is somewhat off topic for this thread, however it looks like you are using some transistors to drive the gate of the FETs kind of like what's called a "Darlington pair". I have not read the spec sheet for your FETs that you are using, but this might not be necessary. You might be able to simplify your circuit and remove those and direct-drive your gate pins. Again, I've never used a 555 timer or some of the other components you are using, so I could be wrong, but typically drive my N-FET gates right from a microcontroller output logic pin.
Here, I have a thread for my build here -> http://forums.thecustomsabershop.com...ustom-Circuits
So we can discuss cleaning my circuit up... I appreciate any knowledge you can give me!
Updated OP with video.
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