New Driver: PD68 "DoubleUp" - 26mm - Double FET - 4*7135

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pilotdog68
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New Driver: PD68 "DoubleUp" - 26mm - Double FET - 4*7135

PD68 DoubleUp – 26mm – Double FET – 4x 7135

This is kind of a weird size since it’s for a specific light. I don’t know how useful it will be to other people, but I’ll share it anyways.

I worked hard to keep it symmetrical, so hopefully you can see that in the design.

  • 26mm
  • Fits Attiny13/25/45/85
  • 2x FETs to handle heat from multiple XHP’s in parallel
  • FETs are parallel, so can be used with 1 or both FETs populated
  • 4x 7135’s in parallel on second PWM circuit
  • Zener Ready
  • 10mm spring pad
  • 3.2mm LED+ passthrough (should easily accommodate 18awg wire)
  • 3.5mm LED- pad
  • 2mm edge keepout on top
  • Scrape-able pad for Pin3 (directly under its label)

It is of course untested until my order arrives

Rev1 (Current)

My Favorite Modded Lights: X6R, S8 , X2R , M6, SP03

Major Projects:  Illuminated Tailcap, TripleDown/TripleStack Driver

Edited by: pilotdog68 on 09/12/2015 - 23:50
pilotdog68
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Reserved

My Favorite Modded Lights: X6R, S8 , X2R , M6, SP03

Major Projects:  Illuminated Tailcap, TripleDown/TripleStack Driver

keithd
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Which light did you design it for?

pilotdog68
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keithd wrote:
Which light did you design it for?

SkyRay/Fandyfire G36

My Favorite Modded Lights: X6R, S8 , X2R , M6, SP03

Major Projects:  Illuminated Tailcap, TripleDown/TripleStack Driver

ImA4Wheelr
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Sweet driver.

You should consider ditching the zener and using a LM2936 instead in a SOT223 package.  Will regulate to a very nice 5 volts and have very, very low parasitic drain.  Can handle up to 40 volts input.  It has built in reverse polarity protection.

It needs a resistor in series with a capacitor going to ground on the output pin.  Your board's existing cap should cover the need for an input cap.

I have these on the way.  I would be happy to test such a board if you designed it.

http://www.aliexpress.com/item/20PCS-LM2936MP-5-0-LM2936MP-IC-REG-LDO-5V...

pilotdog68
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Does it have an advantage in non-eswitch applications?

Frankly, I don’t know enough to start incorporating other components, I basically just physically rearrange existing circuits. If I can find a footprint, and you can show me how to connect it, I’d be happy to do the work in Eagle. Feel free to shoot me a PM with a simple diagram if you have one.

My Favorite Modded Lights: X6R, S8 , X2R , M6, SP03

Major Projects:  Illuminated Tailcap, TripleDown/TripleStack Driver

keithd
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This sounds like a good driver for a J20 with XM-L2s.

ImA4Wheelr
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The LM2936 does provided much more benefit to momentary switch lights.  Of course, a momentary switch could be connected to the OTC pads on your board.

In a clickie light, it should have much less voltage drop out during operation.  How much more voltage/current that would make available to the emitter, I don't know.  The longer the light is on, the more important the loss would be.  In a light that someone is trying to eliminate every little loss (e.g. resistance mods, etc), it will be considered a benefit.

The MCU would also get much more consistent voltage.  I've been very impressed with how solid it's voltage output is.

I don't have Eagle on this computer.  I'll PM you the info I have so far when I get on my other PC.

pilotdog68
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Thanks for the info. I’ll try to include that in future designs.

I’ll probably do a 20/22mm version of my 17mm driver next.

My Favorite Modded Lights: X6R, S8 , X2R , M6, SP03

Major Projects:  Illuminated Tailcap, TripleDown/TripleStack Driver