See Slide 20 ...
http://www.ti.com/lit/ml/slap119a/slap119a.pdf

Adapting to environmental change
• We must calibrate each pad at startup
Components vary
Mechanical assembly (glue, etc.) varies
• We need to dynamically adapt that calibration
Capacitance and the input threshold vary with temperature
Supply voltage and other parameters may drift
• We need to avoid adapting to the wrong thing
Hands waving near the touch pad should not cause the threshold to rise unduly
Obviously we should not adapt when a finger is detected
We should freeze adaptation of all keys, when any one is detecting
Adapt slowly, as real changes occur slowly
Adapting downwards faster than we adapt up helps tolerate waving hands
• A fixed threshold above the base capacitance works OK for touch switches

Did you implement the "Charge / Discharge Capture TAR" Sending method?

 

Thank you everyone for enthusiastically helping me!
Perhaps I have found the cause of the problem. The problem at ti's driver does not update the changes of the environment, the uart module can not receive big data continuously, this make microcontroller wrong.
May exist emi noise impact pad touch!
I will study about it, and share in the future!

 

See Slide 20 ...
http://www.ti.com/lit/ml/slap119a/slap119a.pdf

Adapting to environmental change
• We must calibrate each pad at startup
Components vary
Mechanical assembly (glue, etc.) varies
• We need to dynamically adapt that calibration
Capacitance and the input threshold vary with temperature
Supply voltage and other parameters may drift
• We need to avoid adapting to the wrong thing
Hands waving near the touch pad should not cause the threshold to rise unduly
Obviously we should not adapt when a finger is detected
We should freeze adaptation of all keys, when any one is detecting
Adapt slowly, as real changes occur slowly
Adapting downwards faster than we adapt up helps tolerate waving hands
• A fixed threshold above the base capacitance works OK for touch switches

Did you implement the "Charge / Discharge Capture TAR" Sending method?

I developed a separate driver to cover all of the things you mentioned, the driver worked verywell, i was test it!
But it not run OK when i deploy device in a number of places with different power network conditions, different loads...
I found the MSP's uart module woking not well when receive big data continuously, it make MSP wrong!
Thanks for your share!
I will study more and share what i know!

 

Couple of things to check.

1. The input of the PSU show your Y capacitor but they don't seem obviously connected to anything except the GND symbol. They would need to be connected to earth to provide the common mode functionality. Are they connected to anything? If not they don't provide any filtering effect.
2. The 0V of your PSU is labelled GND_MCU but also has a off page connector to GND, is this the same GND as the bottom of your Y capacitors? i.e have you physically connected them as they have the same net name? All the microcontroller circuit also seems to use GND rather the GND_MCU so its a little confusing.

 

Couple of things to check.

1. The input of the PSU show your Y capacitor but they don't seem obviously connected to anything except the GND symbol. They would need to be connected to earth to provide the common mode functionality. Are they connected to anything? If not they don't provide any filtering effect.
2. The 0V of your PSU is labelled GND_MCU but also has a off page connector to GND, is this the same GND as the bottom of your Y capacitors? i.e have you physically connected them as they have the same net name? All the microcontroller circuit also seems to use GND rather the GND_MCU so its a little confusing.

Thanks for reply!
1. My switch is designed witch 2 pcb, the 2nd picture show schematic of touch panel, firt and 3rd picture show board board.
2. The lable GND_MCU have connected to lable GND. In my area almost no earthing wire.
3. According to my survey, it seems that noise comes from spark when turning on or off the mechanical switch, can you give me advice to avoid this noise?
Thanks!

 

Thanks for reply!
1. My switch is designed witch 2 pcb, the 2nd picture show schematic of touch panel, firt and 3rd picture show board board.
2. The lable GND_MCU have connected to lable GND. In my area almost no earthing wire.
3. According to my survey, it seems that noise comes from spark when turning on or off the mechanical switch, can you give me advice to avoid this noise?
Thanks!

I assume that by mechanical switch you mean the relay?
If you have no load connected to the relay does the circuit operate as expected?