ESD performance with CY7c65642

[Anonymous]

Hi,

   

I have a carrier board with touchscreen and SMARC connector. The touchscreen is connected via USB hub (USB2.0 full speed)

When I connect a SMARC module with SMSC2532 USB hub controller from Microchip and zap the touchscreen with ESD 8kV air discharge, I see no problem with the touch.

   

When I connect a SMARC module with CY7C65642 USB hub controller and perform the same ESD test, the touch screen stops working.

       

I could find the ESD performance of the microchip hub which conforms to JEDEC class 3A but I cannot find any information for the CY7C65642 hub controller.

   

Please guide.

[Anonymous · Accepted solution]

Hi Sinha,

   

Basically CY7C65642 has internal ESD protection diodes on all I/O pins.

   

These diodes are capable of protecting ESD against up to 2.2KV which confirms to JEDEC class 2.

   

External ESD protection diodes need to be added for extended ESD protection.

       

Regards,

   

Anil

[user_3067666]

Hello Sinha,

Did this solve your touch problem?

Kind regards,

Gert