AM3352: ESD Test Issue

Hello Ning Li, 

Thank you for the query.

The diagram does not help me understand the system level implementation to review.

Ning Li said:

1. contact discharge method:±6KV

2.air discharge method:±12KV

You mentioned the board is failing at 6 KV contact and 12 KV air discharge.

I assume you have tested the ESD in steps and can you share the voltage level board is passing.

Regards,

Sreenivasa

Hi  Kallikuppa,

Only contact 2KV  level can be pass the ESD test.Customer want to know if the schematic have any issue or not?

Thanks

Hello Ning Li, 

Thank you.

ESD failure is a combination of system design, layout and implementation of protection devices.

I am not sure if i have the required information to comment.

I would suggest adding an ESD protection device and performing the tests.

The ESD PL could suggest a part number.

regards,

Sreenivasa

Hi Kallikuppa,

Customer want to know is there a way to restore functionality by resetting the touch hardware module?They have try to do this,but no useful.

Thanks

Hello Ning Li, 

Thank you.

Ning Li said:

Customer want to know is there a way to restore functionality by resetting the touch hardware module?

Can you please ask customer to elaborate what he meant by restore the functionality?

Regards,

Sreenivasa

They want to  through the register to reset the touch function when the esd is failure.End customer is waiting the product ,so pls kindly help to it.

Thanks

Hello Ning Li, 

Thank you.

What is the failure customer is seeing? Is he not able to access the ADC after ESD. Does it become normal after power cycle.

Has customer tried testing with ESD diodes populated.

Please note that with limited or no details available on the system and the design i can only provide some guidance.

Regards,

Sreenivasa

Hello,

After the 2KV contact ESD test,the touch is unnormal.And when the power on again,the touch function is normal.So they want to through the register to reset the chip after ESD test.Pls kindly help to check whether is useful or not?

BTW,as Confidentiality agreement,the system design they can not provide us.

Thanks

Hello Ning Li, 

Thank you.

Please refer to the below thread.

(+) Touchscreen controller reset - Processors forum - Processors - TI E2E support forums

Customer will have to add additional filtering or protection on the system level to ensure the ADC does not get affected.

Regards,

Sreenivasa

Hello Ning Li, 

Did you have a chance to add additional protection and perform additional tests?

Regards,

Sreenivasa

Hi Sreenivasa ,

Customer now can not to add additional protection.They will add the esd protection in the Gen2.

Thanks

OK Noted