topic Re: KL16 Change in Captouch count with change in Temperature in Kinetis Microcontrollers

KL16 Change in Captouch count with change in Temperature

amitmehta — Mon, 02 Jul 2018 11:25:05 GMT

i have added external overlay for captive input, TSI module is configured in auto noise mode. Controller works properly in normal condition but when there is change in temperature value of count decrease with decrease in temperature and increase with increase in temperature. Counter value difference is going beyond 8000 w.r.t. Calibration value.

Is there any way to get touch input while avoiding any false touch input. So that our application can work properly.

Below is configuration done for TSI module :-

TSI Module Setup Parameters
Parameter	Value
Scanning Time Per Channel	20ms
Delta Value	2000
Pre-scalar	16
Reference Charge	32uA
NSCN	18
Auto Noise Mode Setup Parameters
Mode	Automatic Noise Mode
Filter Bits	3 filter bits
Series Resistance	32 kΩ

Re: KL16 Change in Captouch count with change in Temperature

vicentegomez — Wed, 11 Jul 2018 19:35:56 GMT

Are you using the TSS library or only the TSI module?

In the library there is an autocalibration function, you can call this function periodically in order to avoid false touch

Regards

Vicente

Re: KL16 Change in Captouch count with change in Temperature

amitmehta — Fri, 13 Jul 2018 07:30:16 GMT

Hi Vicente,

I am using TSI library API which is available are available in SDK

SDK Version: KSDK 2.2.0 (2017-03-21) for

Device: MKL16Z64xxx4

OS: Windows, Toolchain: IAR Embedded Workbench for ARM

Re: KL16 Change in Captouch count with change in Temperature

vicentegomez — Wed, 18 Jul 2018 14:36:07 GMT

I do not know if you can add Freemaster in order to see the baseline value and check if this is increasing due the temperature if this is the case you can reset the baseline making a calibration to set a new value for the baseline

Hopes this will help you

Re: KL16 Change in Captouch count with change in Temperature

amitmehta — Mon, 23 Jul 2018 04:49:33 GMT

Hi,

I am using KL16 in custom made board so i don't think it is possible to add freemaster. Resetting base line ? i don't get it do you mean perform software reset or update calibration value ? If so on what basis should i update ?