ATMEL capacitive touch breakout boards

Ron Czapala

https://learn.adafruit.com/adafruit-capacitive-touch-sensor-breakouts

Adafruit has some nice capacitive touch sensors - a momentary, a toggle, and a 5-Pad Momentary

The Momentary version can be configured for "Fast" mode (default) or low-power mode. Fast mode requires 0.5mA. Low Power mode requires just 50uA.

By default, the toggle sensor is configured for infinte time-out. it will stay on until you touch the sensor to turn it off.
It also supports a configurable time-out to turn off the output automatically after a delay.
To select this mode, cut the 'TIMER' jumper and connect a resistor & capacitor to the TIME pin.

erco

Cap sensors are neat and magical. I played with one here: http://forums.parallax.com/showthread.php/156497-2.79-8-Channel-Capacitive-Keypad?p=1282705&viewfull=1#post1282705

Cheap on Ebay: http://www.ebay.com/itm/1x-XD-34-TTP224-4-Way-Capacitive-Touch-Switch-Digital-Sensor-Module-Board-Plate-/390977396193

My best use of cap sensors yet: https://www.youtube.com/watch?v=3e92B8JNNns

Ron Czapala

erco wrote: »

Cap sensors are neat and magical. I played with one here: http://forums.parallax.com/showthread.php/156497-2.79-8-Channel-Capacitive-Keypad?p=1282705&viewfull=1#post1282705

Cheap on Ebay: http://www.ebay.com/itm/1x-XD-34-TTP224-4-Way-Capacitive-Touch-Switch-Digital-Sensor-Module-Board-Plate-/390977396193

My best use of cap sensors yet: https://www.youtube.com/watch?v=3e92B8JNNns

I also like the looks of this one on Futurlec - uses the IQS127D

Two digital outputs are provided, one for Touch and the other for Proximity

http://www.futurlec.com/Touch_Pad.shtml

Ron Czapala

Got the Adafruit sensors today. They trigger when my finger gets about 1/4 of an inch away from the pad.

When behind a plastic project enclosure box, a firm press works.

I am pleased with how well they work.

erco

Great info Ron! It's pretty sweet that both those sensors can discriminate between proximity and touch. Love that LED on the Futurlec version, might have to grab some. Touch pads are cool and high tech, but of course they lack tactile feedback. I have found that feedback from an adjacent LED and/or sound chirp is very helpful.

"Another" processor I used in the video in post #2 has integral touch sensing capability on 11 of its GPIO pins. A built-in function reads the field on an attached plate, pad or wire and returns a number. With calibration, you could also determine proximity vs touch. Not bad for a $4 chip.

Ron Czapala

erco wrote: »

Great info Ron! It's pretty sweet that both those sensors can discriminate between proximity and touch. Love that LED on the Futurlec version, might have to grab some. Touch pads are cool and high tech, but of course they lack tactile feedback. I have found that feedback from an adjacent LED and/or sound chirp is very helpful.

"Another" processor I used in the video in post #2 has integral touch sensing capability on 11 of its GPIO pins. A built-in function reads the field on an attached plate, pad or wire and returns a number. With calibration, you could also determine proximity vs touch. Not bad for a $4 chip.

The single pad (momentary and toggle) have an LED which shows through a hole in the PCB. A trace can be cut disabling the LED if desired,

While the board detects proximity as well as touch, there is only one output pin which reflects either/both.

I will probably use a toggle sensor with the Sharp 8A solid state relay (which Parallax sells) to create a table lamp touch switch. Very low current draw - 3 AAA batteries should last quite a while.

Ron Czapala

Here is short video using the Adafruit capacitive toggle touch sensor and a Sharp 3A solid state relay.

Add a 4.5V (3 AA cell) battery and a 220 ohm resistor and you've got a touch sensitive 125VAC switch.

Draws about 15.6 milliamps (or 8 milliamps at 3V) when turned on.

erco

Ron Czapala wrote: »

I will probably use a toggle sensor with the Sharp 8A solid state relay (which Parallax sells) to create a table lamp touch switch. Very low current draw - 3 AAA batteries should last quite a while.

Or for $1.09 free ship: http://www.ebay.com/itm/1-Way-Touch-Control-Sensor-Table-light-Parts-On-off-Bulb-Lamp-Switch/261489643788

Ron Czapala

erco wrote: »

Or for $1.09 free ship: http://www.ebay.com/itm/1-Way-Touch-Control-Sensor-Table-light-Parts-On-off-Bulb-Lamp-Switch/261489643788

Hmmm - says 50Hz - not 60Hz. Wonder it works in U.S. Wiring diagram hard to read. Great deal if it works here!

http://www.answers.com/Q/What_is_50hz_and_60hz

erco

Will advise!

Ron Czapala

erco wrote: »

Will advise!

I guess you ordered one/some...

Also says AC 220V +/- 10% - think this is for Europe, etc
This seller has one opened up - circuit looks unsubstantial - I guess the flat. vertical thing is a triac
http://www.ebay.com/itm/Table-light-Parts-On-off-1-Way-Touch-Control-Sensor-Bulb-lamp-Switch-Black-/121347212401?pt=LH_DefaultDomain_0&hash=item1c40db8471

This one sells 110V or 220V - except they are 3-way AND

not suited for energy-saving lamps and LED lights

- http://www.ebay.com/itm/1Pc-AC-110V-220V-Table-Desk-light-3-Way-Touch-Control-Sensor-lamp-Switch-S7-/321624234794?pt=LH_DefaultDomain_0&var=&hash=item4ae24c5b2a

Almost every bulb in my house is LED. Philips has a nice 40/60/100 3-Way LED now http://www.homedepot.com/p/Philips-40-60-100W-Equivalent-Soft-White-2700K-3-Way-A21-LED-Light-Bulb-453340/205427985
Bought one - like to get more

erco

For just a buck, I'm a gamblin' man. If it works, I'll share. If not, I'll destroy the evidence and deny we ever had this conversation...

erco

erco wrote: »

For just a buck, I'm a gamblin' man. If it works, I'll share. If not, I'll destroy the evidence and deny we ever had this conversation...

Arrived today and it works fine on 120VAC/60hz. No wiring diagram included, but I took a closer look at the original listing. The photo shows hookup details etched in the black plastic case, which mine didn't have. The photo was also reversed and required flipping and zooming in to read, but it worked fine. Black wire is common, to 120VAC and the light bulb. Red wire to other 120VAC connection. White wire to other bulb connection. Yellow wire is touch sensor, connect to any metal object. It worked when I just touched the brass wire connector. A closer look at the photo and is says 120V/240V and 50hz/60hz. Not sure what "+/-10%" brings to the party.

It's for incandescent bulbs, obviously. I did a quick test with a CCFL which didn't work. I almost tested with my one LED bulb but I chickened out.

I'll buy that for a dollar! (Robocop)

Ron Czapala

Thanks for the update! They could have been a little more accurate in their description...

All of my table lamps are LEDs so I guess I'll pass.

- Ron

erco

Don't make me plug in my LED lamp, Ron!

Anyone have any input about potential damage? Or maybe the performance will just suffer since the current levels are so low?