Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Touch Controller Sensivity Adjustment

Status
Not open for further replies.
G

gauravkothari23

Advanced Member level 2
Joined
Mar 21, 2015
Messages
640
Helped
5
Reputation
10
Reaction score
4
Trophy points
1,298
Activity points
6,922
HI all,
i am trying to make touch keypad using MTCH108 Capacitive Touch controller.
I have build the circuit, but the issue what i am facing is some of the pads shows less sensitivity than others. in total i have 10 touch pads, so i have used MTCH108 and MTCH102 to interfacing 10 touch pads.
and i have buttons from 0 to 9. 0 and 1 are interfaced to MTCH102 and 2 to 9 are interfaced to MTCH108. i am facing a problem in pad 6. the Sensitivity of pad 6 is quite low as compared to other pads from 2 to 9 as they all are connected to same IC MTCH108. can anybody please let me know what can be the issue.

- - - Updated - - -

Here is my attached image of touch pad PCB.
 

Attachments

  • Touch Pad.jpeg
    Touch Pad.jpeg
    122 KB · Views: 59

Hi,

A riddle.

We don't see your circuit, nor do you tell whether you read the datasheet, especially the section "sensitivity adjustment".
We don't know which of these schemes you use.
We don't know wheter you have read and followed these application notes:
* “mTouch® Sensing Solution Acquisition Methods Capacitive Voltage Divider” (AN1478)
* “Techniques for Robust Touch Sensing Design” (AN1334).

Klaus

Added: now we see the circuit..
But:
in total i have 10 touch pads,
Click to expand...
I see 12 touch pads..

Pad6: shows lengthy wiring, crossing at least 5 other sensor pads.....
 

KlausST said:
Hi,

A riddle.

We don't see your circuit, nor do you tell whether you read the datasheet, especially the section "sensitivity adjustment".
We don't know which of these schemes you use.
We don't know wheter you have read and followed these application notes:
* “mTouch® Sensing Solution Acquisition Methods Capacitive Voltage Divider” (AN1478)
* “Techniques for Robust Touch Sensing Design” (AN1334).

Klaus

Added: now we see the circuit..
But: I see 12 touch pads..

Pad6: shows lengthy wiring, crossing at least 5 other sensor pads.....
Click to expand...

Yes, i have gone through the datasheet and also the application notes before designing.
But yes i agree... the trace length of pad 6 is quite long, which created a problem.
i have shorten the pad length and the things are working great.
thanks a lot for your help'
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top