Well i am for sure no expert. I just did start looking into it. Mainly what i looked into is what they use for touch activated stuff. Since it related to a touch sense mosfet. never really looked into spikes. Hell i am not even sure i will beable to solder the 0402's but i will give it a shot. I plan on doing a few tests might even video it. Do the moon walk on some carpet and try to hit the touch pin with a ESD spike and see what happens.
Tired of manual switches? Simple Touch switch pass thru for under $15.00
- Thread starter Scubabatdan
- Start date
- th_trl_thread_readers 0
- Status
Hehe, I've done that, my own personal ESD tests. Anyone looking in would think I had lost my little kitty mind, moonwalking in circles on the carpet. Believe it or not, you can spend thousands of dollars on a machine that produces static discharge specifically for electronics ESD testing.
"The ScubaProx" Gotta love it. I may have to try this out !
Would this schematic of components work with a P channel instead of an N-Channel if you switched the prox chip + and - ?
Would this schematic of components work with a P channel instead of an N-Channel if you switched the prox chip + and - ?
Last edited:
You might be limited to an N-channel for that particular chip. The logic is reversed for a P-channel, low is on and high is off. For an N-channel, low is off and high is on. You'd have to look at that chip's data sheet, depends on how it handles the logic output.
No you cant switch that one around. If i remember right ( been awhile since i have read the Data sheet ) The output on the ATMEL cant be taken low. Basicly that just means it wont put out a ground which the gate on a P Channel requires. That is why i was going to design a new circuit for use with a P Channel. You could add a small low amp N channel to the mix. Output to the gate on the N channel then the Drain would go to the P channels gate. Anyways thats what the plan was not sure if there is a better way to do it. But as it is, that schematic wont work with a Pchannel.
I wanted to incorporate a TI boost ptn0405 to it. If you come up with a solution I would be interested in it.
How do you plan on setting up the circuit. Do you plan on etching a board for it. The Atmel chip is really pretty small to be soldering all those wires to. I can design the circuit that can be etched into a board i just don't have the time to make the board and test it all out to make sure it works. But if you want , i can whip out the circuit real quick. Really i wouldn't change much as far as the Atmel chip goes i would keep it the same as Dans final version of it and just transfer all that stuff over then add a small N channel off it's output to power the gate on the P channel. something like a 65cent part i believe. Kinda sucks you cant really breadboard this stuff , but thats how it goes with the small SMT/SMD parts.
I was going to mention logic can be reversed quite easily with a small signal N-channel driving a P-channel power FET. I do it all the time. But, that might be a little more than the OP is willing to mess around with.
I breadboard SMD stuff by making a small PCB with header pins that allows me to breadboard individual components or subcircuits. In fact, I'm working on a new design right now I'm breadboarding in that manner. That way, I can be sure questionable parts of the design work as expected before spending money on a manufactured PCB. Unfortunately for me, my PCB manufacturing skills are nowhere near that of Java_Az's.
I breadboard SMD stuff by making a small PCB with header pins that allows me to breadboard individual components or subcircuits. In fact, I'm working on a new design right now I'm breadboarding in that manner. That way, I can be sure questionable parts of the design work as expected before spending money on a manufactured PCB. Unfortunately for me, my PCB manufacturing skills are nowhere near that of Java_Az's.
So if I understand correctly the circuit shown by Dan will basically be the same, but a P-Channel will be on the positive side, and the N-channel on the ground side will be connected to the P-channel?
I really didn't have a circuit plan worked out for an N and P chan mosfet connected to the prox chip and TI booster.
As far as putting it together i have cobbled together 0402 reisistors on SON 3.3mm×3.3mm P channel mosfets(TI CSD25401Q3) and mounted it to a ptn04050c booster.
I know Dans design has more complex parts and small sizes to deal with, but I am just needing a diagram of a circuit layout to try out.
I'm not that good at figuring out what component requirements are needed as I failed my electrical engineering class. lol
I will need to study the Amtel chip datasheet. So will the n-ch connect to the output of the Amtel chip and the pchannel will connect to the n-ch with the p-ch firing the booster?
Yes kinda sorta if your talking about the first circuit posted in this thread you would need a Pchannel with pretty much the same specs as the NChannel and the same source voltage for the resistor values to work. It can be a bit confusing because later on in the thread there is a captive touch circuit that Dan did, thats a whole different ball game . The first is just a basic touch with a mosfet and a couple resistors that one can just be reversed when using a P channel. I made a schematic a page or two back with the P Channel. I dropped the gate resistor off it since the Mosfet listed in the schematic has build in ESD protection also used a different source to gate resistor that seemed to work best with the PChannel mosfet part number that i have listed in the schematic. The one i did is for stacked batteries so it is made for a nominal 7.4 volts. If your using a single battery a different Pchannel mosfet with a lower gate voltage should be used. i guess i should have been more clear on the fact you could just slap anyold Pchannel in and expect the resistor values to work you also have to consider voltage mainly we see 3.7 or stacked 7.4. it can make a difference.
I was thinking about doing that today i just got a couple 50 strips of .100 pin headers. I might have to make up a few boards with the popular footprints. Still kinda a pain to go threw all that but at least it gives you an idea of how the circuit would work.
Yeah i can do a schematic i think will work for you. If you can solder a 0402 i think you will be able to handle it. If i don't have it up tonight i will have it posted sometime tomorrow.
Yes, it can be a pain. For someone with abilities such as yours, you can probably just make a PCB that supports your whole design. If it has bugs, then build a new board with the changes and test again.
I've been trying different things in an attempt to improve my PCB making abilities, but I just can't seem to get there. I pretty much have to pay to get them made. I can make the ones I need for breadboarding but that's only to verify any questionable portions of my design prior to paying for manufactured ones. It gets expensive fast when you order PCBs that can only be used as coasters. It has happened before, despite my best efforts.
Thanks Java! Those tiny resistors are a pain to solder. They like to stick to the iron if you don't pinch them down with something.
Hey have you seen one of these?
Here you go, Pretty sure this will work for a single battery
yeah the multi-meter tweezers are nice wish i had a pair.
EDIT: here it is in the light color scheme, Might be easier to see for some. Also changed a couple resistor values
EDiT2: Here is one figured for batteries in series (7.4volts). Just two resistor values changed and a beefier Pchannel was put in. Also should have said This is all based on DANS work i just added a mosfet and resistor...So credit should go to him for figuring out the Atmel chip.
Disclaimer: Use of this circuit, is at your own risk. As with any and all circuits i create , meddle with , transfer, modify or design I cannot guarantee my soberness while working on them. I do however find it extremely helpful if you have a extra large ice cold beverage on hand while testing. It can be particularly helpful in dousing small fires. But in the more likely event of a fully functional project you will have something to toast your success with, Peace and Happy Modding
yeah the multi-meter tweezers are nice wish i had a pair.
EDIT: here it is in the light color scheme, Might be easier to see for some. Also changed a couple resistor values
EDiT2: Here is one figured for batteries in series (7.4volts). Just two resistor values changed and a beefier Pchannel was put in. Also should have said This is all based on DANS work i just added a mosfet and resistor...So credit should go to him for figuring out the Atmel chip.
Disclaimer: Use of this circuit, is at your own risk. As with any and all circuits i create , meddle with , transfer, modify or design I cannot guarantee my soberness while working on them. I do however find it extremely helpful if you have a extra large ice cold beverage on hand while testing. It can be particularly helpful in dousing small fires. But in the more likely event of a fully functional project you will have something to toast your success with, Peace and Happy Modding
Last edited:
Here you go, Pretty sure this will work for a single battery
yeah the multi-meter tweezers are nice wish i had a pair.
EDIT: here it is in the light color scheme, Might be easier to see for some. Also changed a couple resistor values
EDiT2: Here is one figured for batteries in series (7.4volts). Just two resistor values changed and a beefier Pchannel was put in. Also should have said This is all based on DANS work i just added a mosfet and resistor...So credit should go to him for figuring out the Atmel chip.
Disclaimer: Use of this circuit, is at your own risk. As with any and all circuits i create , meddle with , transfer, modify or design I cannot guarantee my soberness while working on them. I do however find it extremely helpful if you have a extra large ice cold beverage on hand while testing. It can be particularly helpful in dousing small fires. But in the more likely event of a fully functional project you will have something to toast your success with, Peace and Happy Modding
That My Sir is above and beyond. I thank you and I hope others can utilize these as well. This thread should be sticked.
Disclaimer: Use of this circuit, is at your own risk. As with any and all circuits i create , meddle with , transfer, modify or design I cannot guarantee my soberness while working on them.
I wouldn't expect any less from Mr. Adams....
cheaper alternative to those smart tweezers' tiny display
here
thought they were pretty cool, and hellacheaper
here
thought they were pretty cool, and hellacheaper
It will just pop the IC as posted. I would at least add a voltage divider for the atmel chip. It will most likely require a dedicated power supply, as these touch IC are very sensitive to noise and voltage. So I would also recommend a cap for the power supply IC. If it were me, I would replace both of the mosfet's and run a single N Channel logic level mosfet, and run that (negative) side to the atty, and positive always connected.
- Status
Similar threads
