Combine Touch switch with Booster

[Dalton63841]

Okay I am still waiting on a couple parts from madvapes, but while I wait I figured I would get a second opinion on the schematic. I drew it up very quickly in Preview, but the goal is basically a one battery setup using the PTN04050C as per breaktru's mod here with a touch switch as per asnider's mod here.

I want to make sure that I didn't screw it up in the process of combining the two, and also if any of it can be simplified. Also, would it be better to have the switch before the booster like this:


Or AFTER the booster like this:

 

[asnider123]

You know, I cannot find anything that wouldn't work in that circuit. You do know the FET you chose is an "n-channel MOSFET" meaning that it switches the negative. I see that you have considered that. I am of those darned common grounds, you could inadvertently find a ground darn near anywhere (especially if your plan is some kind of tube or flashlight mod).

I would be tempted to find a "P-Channel" MOSFET myself. But I am no expert with this TI booster. You should shoot a question to breaktru .. I believe he either has or is working on combining those elements and can better steer you toward a good conclusion.

Hope that helps

Alan

 

[Dalton63841]

Thanks! I will jump over to breaktru's site and see if he can take a look at it. Far as I can tell it should work...Do you think is would be better to put the touch switch stuff before(1st image) or after(second image) the booster? Either way it is getting a master switch immediately after the battery.

 

[asnider123]

Thanks! I will jump over to breaktru's site and see if he can take a look at it. Far as I can tell it should work...Do you think is would be better to put the touch switch stuff before(1st image) or after(second image) the booster? Either way it is getting a master switch immediately after the battery.

I feel the mosfet should probably be before the booster, as you have in your diagram #1. You realize (that's in your quote above) that you really need a master switch because the circuit will be drawing a little current all the time, even when not firing, because of the MOSFET. You may consider a small led on the master switch, just to remind you to turn it off when not in use.

Also, someone told me (perhaps it was you) that the 10 meg resistor in the touch switch would be better as a 100 meg, which would make the touchpad more reliable. With my 10m resistor, I have to sometimes wet my finger (lick it) to provide adequate conduction, it depends on skin moisture to trigger. Apparantly a 100m resistor solves this prob.

Yes, it should work so long as it is going in a non-conductive housing.

 

[Dalton63841]

So before is better then...I kindof assumed that it would. Yea I am putting a master switch in there to prevent the draw from the FET. I have done alot of homework and reading on this, both on this forum and all the datasheets for the chips involved. I am waiting to have breaktru check it out just to be 100%.

Also I did manage to get my hands on a handful of 100M(and many others in a assorted 500 pack) resistors, and I found the CAPS for the booster, so I am just waiting on my box from madvapes. (The 2xAA boxes from RS suck.)

 

[asnider123]

So before is better then...I kindof assumed that it would. Yea I am putting a master switch in there to prevent the draw from the FET. I have done alot of homework and reading on this, both on this forum and all the datasheets for the chips involved. I am waiting to have breaktru check it out just to be 100%.

Also I did manage to get my hands on a handful of 100M(and many others in a assorted 500 pack) resistors, and I found the CAPS for the booster, so I am just waiting on my box from madvapes. (The 2xAA boxes from RS suck.)

Where did you find the resistor assortment? Was it expensive?

2-AA boxes, what's wrong with radio shack ones? Never tried them. I buy my battery boxes on Ebay from hongkong .. takes a while but 1/2 price .. I'm not in a hurry

I sure am interested in seeing your most exciting results. Please post pics and perhaps a tutorial on assembly.

Alan

 

[Dalton63841]

Where did you find the resistor assortment? Was it expensive?

2-AA boxes, what's wrong with radio shack ones?

I found the 500 pack of resistors from Radio Shack for $10. ~30 of about every possible size of resistor HAHA. I probably will only use ~10 resistors out of the bag, but who knows when I may need them.

I don't like the 2xAA boxes from Radio shack because unlike the 3xAA boxes they don't have a built in slide switch(makes things easier when it's already there) and also you have to put a screw in the lid to keep the lid on the box.

I will be sure to post about it with pics. Still waiting on the box, and the mosfets to get to me. My mail has been weird the last few days.

 

[outofjuice]

i have to know how this will turn out... was thinking of doing something like this for the dream gold mod

 

[Dalton63841]

i have to know how this will turn out... was thinking of doing something like this for the dream gold mod

Haha Frankly I am surprised I have not seen it on here yet(or perhaps I haven't dug deep enough), but I am very excited about it. Just waiting for 2 parts which should be here within the next few days. I figure if I can fit this into a 2xAA box, then next I am gonna work on a bottom feeder with the same setup. Obviously THAT wouldn't fit in 2xAA, but Im gonna see how small I can keep it.

 

[asnider123]

The mosfets aren't there yet? mailed them tuesday morning .. gotta be there by tomorrow fer shure, yer only 1 state away

 

[Dalton63841]

The mosfets aren't there yet? mailed them tuesday morning .. gotta be there by tomorrow fer shure, yer only 1 state away

My mail lady quit/got fired/retired/not sure a few days ago so they have to have a carrier from the next town over come do her route in the afternoons. All of my mail has been getting to me late.

 

[asnider123]

My mail lady quit/got fired/retired/not sure a few days ago so they have to have a carrier from the next town over come do her route in the afternoons. All of my mail has been getting to me late.

See, you should have made her a boxmod, worked for me

 

[Dalton63841]

See, you should have made her a boxmod, worked for me

Haha actually she was a sweet woman. Always stopped and talked to everyone who was outside when she delivered their mail. We actually had a talk about one of my mods, but she had no interest in getting one for herself. I hope the mail straightens out soon. At this moment I have stuff from Madvapes, KBV, a Vapemate I got from the Classifieds here, and a new Provari all coming to me. Needless to say I'm set back for a while...

 

[Dalton63841]

Just got the FET's in the mail a couple hours ago. Just waiting on the box now. Think I am gonna start wiring it together today and so I can just drop it into the box and solder a couple of points once the box gets to me.

 

[asnider123]

Just got the FET's in the mail a couple hours ago. Just waiting on the box now. Think I am gonna start wiring it together today and so I can just drop it into the box and solder a couple of points once the box gets to me.

Dja get a breadboard? Makes testing much easier

 

[Dalton63841]

Dja get a breadboard? Makes testing much easier

I sure don't. Something I need to invest in though for sure. To be honest I haven't really done much in the way of electronics, aside from building PC's, since I was in the Navy back in 2003 at the Naval Nuclear Power Training Command. I forgot how much fun, and how frustrating, this stuff can be.

I got everything put together. All I got to do is solder the atomizer connector and hook up the battery connectors. Then of course put holes in the box for touch surfaces and the atty connector and POT. So far it looks like it will fit. Might even be able to squeeze in a very simple charging port, doubt that one though.

One thing I did notice is I was wrong about the 100M resistor. The assortment came with 10M resistors though, so I have 3 in series for ~30m. According to breaktru, 20-22M should be sufficient, so I am fairly confident this will do nicely.

 

[AttyPops]

The assortment came with 10M resistors though, so I have 3 in series for ~30m.

Just making sure you're putting them side by side (parallel)... so you don't get ticked off when done........otherwise the resistances add: not what you wanted. I think you're doing it correctly, just said series rather than parallel by mistake, but I posted to be sure.

 

[Dalton63841]

Just making sure you're putting them side by side (parallel)... so you don't get ticked off when done........otherwise the resistances add: not what you wanted. I think you're doing it correctly, just said series rather than parallel by mistake, but I posted to be sure.

If I wired 3 resistors in parallel, wouldn't that equal a resistance of ~33k ohms? I put them in series so that they add together to give me 30M ohms...Or am I backwards?

Parallel --- 1/R1 + 1/R2 = 1/Rtotal
Series --- R1 + R2 = Rtotal

 

[AttyPops]

Yeah you're correct. I mis-read and thought you had 3 100M and wanted 33m. It was a brain cramp. I even quoted the 10. Some days I shouldn't get out of bed......

3 100's in parallel would be 33
3 10's in series is 30

nm. Hate it when I mis-read. You had 100m in the previous sentence, and 10m in the next and I had a brain fart.

Although I'm still unsure as to why you don't use 2 10's for a total of 20 if breaktru said that's it's a range or 20-22....now that I re-read it. Nomatter. Like I said... I had a brain cramp. Ignore.

 

[Dalton63841]

Yeah you're correct. I mis-read and thought you had 3 100M and wanted 33m. It was a brain cramp. I even quoted the 10. Some days I shouldn't get out of bed......

3 100's in parallel would be 33
3 10's in series is 30

nm. Hate it when I mis-read. You had 100m in the previous sentence, and 10m in the next and I had a brain fart.

Although I'm still unsure as to why you don't use 2 10's for a total of 20 if breaktru said that's it's a range or 20-22....now that I re-read it. Nomatter. Like I said... brain cramp.

Haha it happens. If I just had one 100M, then I wouldn't need to use the 10M's at all. I am still seeing if I can scavenge one somewhere.