I'm modding my xbox's and i wanted to try and make a mod where the eject and power buttons are sesative like the ipod buttons. I'v alreayd searched here and have come up with this http://forums.bit-tech.net/showthread.php?t=19614&highlight=pressure+switch but I didn't get alot of answers. How would you reccomend i go about build a curcuit and what materials do i need to make one of my own. I was thinking about using the plastic from an old keyboard 3 layers(contact 1, spacer, contact 2) it may or may not work. suggestuons?
You're looking for a touch sensitive switch, not a pressure switch. Very different things! Have a look at Qprox's chips: http://www.qprox.com/products/touch.php
OT but at work, we weigh powders, and I want to try and automate it (= money for me ) Cant find anywhere selling small scales/some kind of weighing module with digital output, capable of 0.1g accuracy though
Hey, is it me or does the rotary touch sensative switch look like copyright infringement against apples pattented scroll wheel?
iv already seen these chips, but does the pad Have to be metal? cause i want to keep the stock look of the xbox button panel. [edit] just read it again... "QT110 family QTouch™ ICs will create sense fields through dielectric surfaces such as plastic or glass up to 100mm (4") thick, and can even turn small objects into sensors. These sense fields can work easily through gloved hands." so i can just place the pad behind the button which is abotu 2 mm thick of plastic and it will still sense it?
aye, apple haven't really invented anything in their life, it pisses me off they moan so much about windows saying oof we had a WIMP OS, but everyones ripping of XEROX who were too stupid to patent it! (and RISC OS was soo much better at the time, anti-aliasing ffs! in '92 on the native text drawing functions!!!!!!) but OT, these sensors need a plate (good conductor) behind an area of capactance (plastic / glass). the plate is normally metal, which means you have problems if u want perfectly transparant things.
hmm oaky this will work! i dont need these buttons to be clear and i can defiantly glue a small peice of metal behind the button
If I remember correctly it was made by a company that specializes in mouse pads (the name was something like Synaptic). Ths same company also makes the touch pad for the creative nomad players. But the company is not allowed to make the rotary pads like what is used on the iPod for any one else. I thought that Apple had pattented it. I've never seen information on the pads development, only its evolution.
I have another question. what does this IC chip output when it sences something? http://rocky.digikey.com/WebLib/Quantum%20Research/Webdata/QT110,%20QT110H%20(QProx).pdf I'v read though the whole thing and never got the info on what it outputs. For my application i just need to send a ground signal to a pin on the Xbox m/b. It would be very nice if this IC sent a ground signal to its #2 pin so i could just hook it up and it would work. But it never told me.... the the most electronical guru butis the pin 8 the input for the switch Code: normal switch--- "____/____ (open switch)" Code: qtouch IC switch--- "ground_____(pin 8)qtouch IC___(pin 2{out})____> to m/b pin." any further explination is needed? tell me.
Google Mettler Toledo scales. Ive worked with them, at 0.1grams. At that sensitivity, you can actually measure the carbonation being released from an open soda can. They have serial interface so you can directly read/control them.
They come in two flavours, active-high & active-low output. Datasheet will give the code for each. QT110 active-low, QT110H active-high and so on. So the active-low will do what you want.
Thanks We have scales there that do 0.001g and are calibrated and accurate.. all the doors and windows need to be shut as just the air makes it wobble... 0.001g accuracy is a bit OTT for what this is needed for, and would make it much more expensive and less flexable in design... One of these could probably do the job: http://www.mt.com/mt/filter_link/pf...DEtUHw3NjY1NTczNzAxLUN8NTY2NTU3MzcwMS1DfAii_D
SO the QT110 active-low will put out a ground signal to the out pin whilst on the dc mod output setting. "2.2.1 DC MODE OUTPUT The output of the device can respond in a DC mode, where the output is active-low (QT110) or active-high (QT110H) upon detection. The output will remain active for the duration of the detection, or until the Max On-Duration expires, whichever occurs first. If the latter occurs first, the sensor performs a full recalibration and the output becomes inactive until the next detection. In this mode, two Max On-Duration timeouts are available: 10 and 60 seconds."
In that mode it's high until the detection has finished, or until it times out, in which case it apparently reconfigures itself, so if you just left a finger on it all the time, you'd have to change it for it to sense anything. Anyway, the top and bottom of it is: Code: Touch:* Release: X * X +v ------------- 0v _____| |______ So if you need an Active-Low signal you could invert that and connect it straight to the X-Box Mobo
I also don't think they really manufacter any of their products. That may be why there is always a finger to point away from apple whenever a product ships late. There strength is their marketting and the brand recognition that they have among people. I'm not an apple fan, but I will say that their products seem to be constructed well.
as i said before im not the biggest electronic guru. How would i invert the signal... also when you say invert you mean change +v to -V
I've used the QT113 with much success. I recommend getting several capacitors in the 1-50 nF range. 10 nF is the standard but you may want to vary it depending on how sensitive you want (there is a high/low sensitivity on the IC but that is a huge leap, the cap lets you make small changes). I'd get several 1 or 2 nF caps, some 5s, 10s, and 20s. That, combined with the high/low setting, should let you find a good level of sensitivity for your application.
