The 3.7v is actually firing the atty. I will look into that p-channel when I can get my hands on one.
Combine Touch switch with Booster
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Would this p channel work? (keep in mind I have no idea what I'm talking about here 
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5pcs P-Channel Power MOSFET Transistor IRF9530 TO-220 | eBay
http://www.datasheetcatalog.org/datasheet/fairchild/IRF9530.pdf
ETA:
Mouser p-channels in TO-220
http://www.mouser.com/Semiconductor...pose/MOSFET-Power/_/N-7h6e2?P=1z0y3dtZ1z0z73r
)5pcs P-Channel Power MOSFET Transistor IRF9530 TO-220 | eBay
http://www.datasheetcatalog.org/datasheet/fairchild/IRF9530.pdf
ETA:
Mouser p-channels in TO-220
http://www.mouser.com/Semiconductor...pose/MOSFET-Power/_/N-7h6e2?P=1z0y3dtZ1z0z73r
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That is strange dont see how it is doing that. Makes me want to dig out my TI sample booster chips and slap one on the bread board. Sometimes seeing is believing. Maybe i will do that after i etch this PCB board. What touch switch setup you using. Maybe it is not fully unlaching after you take your finger off it.
If you look at the first post in this thread, I have been trying the first image, and every possible variation on that. Like I said, breaktru actually knows WHY it is happening the way it is. I'm just not good at explaining.
Would this p channel work? (keep in mind I have no idea what I'm talking about here
5pcs P-Channel Power MOSFET Transistor IRF9530 TO-220 | eBay
http://www.datasheetcatalog.org/datasheet/fairchild/IRF9530.pdf
ETA:
Mouser p-channels in TO-220
Mouser Electronics - Electronic Component Distributor MOSFET Power
It might get a bit hot. you really want to look for a RDS on gate voltage typ of 2.5 volts. That one you posted is 3.8 volts. A single battery will get to around 2.75 volts before protection kicks in. So a little under that for RDS ON is what you want.
I believe it , I am always doing stuff on the bread board and expecting one thing i get another. Looking at the first post i would think that would work. It has to be something to do with the inductor i believe. I just tried to slap the booster chip in the bread board but it dont fit. Maybe i will mess with it tomorrow i dont feel like soldering tonight.
Breaktru points out the issue here. My own testing showed that the 04050C has the same hangup.
I happened to be doing some bread-boarding with the ptn4050c today, and I thought I would give this a try. It seems to work fine for me using the first diagram from the first post (I used a 100M resistor between Gate and Source). I get the expected voltage at the atty connector when touch circuit is closed, and it drops away to nothing as expected when it is open. Is there something else I should be checking for? I can't find a problem with this setup, but perhaps I have one and am blind to it.
Okay now you are just making my head hurt... I have some more, different, N-channels. I will look into it this evening and see what happens.
If you are using the circuit posted w/ mosfet at the atty you are breaking the negative at the Atty and leaving the 04050c powered all the time. It's the negative to the booster that is a problem. Even with feeding all of the negative points through the mosfet.
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Exactly, and in that configuration, the booster still runs down the battery correct?
Nuck used N-channels for all his Fistpacks.
The problem most likely is that huge resistor you are using, it just ain't 'pulling down' properly leaving the mosfet in a semi-open state (floating).
Why don't you try Raidy's original values?
Willy, the only prob with that circuit (at least for me) is that the 4m resistor is not enough. Probably has something to do with my skin conductivity or something. If I lick my finger, it works fine. That's why I put a 10m instead of the 2-4m.
Well I WAS gonna test this... However my soldering iron decided to crap out. No testing tonight.
10M sounds fairly reasonable, but when talk goes to 30 - 100M I think that's were these problems start.
If you've noticed N-Channel mosfets have always been used with almost every reg out there, including the booster and the 08100, but usually you see 10k (or less) pull downs.
The other variable is how do these large values affect efficiency, especially in a single cell mod? There is no free lunch, how do they influence the final output at the atty and what effect do they have on the cells capacity? These mosfets aren't simple on/off devices, they need to ramp up to full saturation to be fully on. Until they do they are operating like a resistor in the high resistance triode region. Large resistor values extend the time spent in this semi-on state.
I never played extensively with touch switches much cuz I don't like the way they work. My finger (or thumb) never comes off the fire button. It seemed awkward to have to always have to make sure to lift my finger completely off the contact.
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