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I used a TTP223 IC operating on 5V. I use the touch IC output (when high) to turn on the LED and (when low) to dim the LED. The LED is operated by the external 5V. It uses only the touch IC output as a signal. I used a blue LED. What is the problem?

It works fine when turned on, but after several days the touch output hangs.

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ESD can be a latchup problem.

Place a thin film (tight) over the sensor, adjust shunt cap for sensitivity then retest.

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  • \$\begingroup\$ I also try 30 PF shunt cap in parallel with Touch Input pin but sensitivity going down , any other Ideas? that helps to solve out the problem. \$\endgroup\$ – Jaimin Sep 17 '19 at 4:29
  • \$\begingroup\$ Eliminate caps for max sensitivity and use glass for lower capacitance. But eliminate static discharge somehow. Separate issues \$\endgroup\$ – Tony Stewart EE75 Sep 17 '19 at 7:35

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