DS90UB948-Q1: ESD TEST

Hello,

For FPD-Link ESD mitigation, we typically recommend ESD protection diodes near the connector.

Additionally, there are a few other methods of ESD protection against the FPD link, such as using a guard ring on the PCB that provides a controlled path to GND away from the traces. The connector itself can also have an effect on how the impulse affects the Link.

Could you describe the ESD test you are trying to meet in further detail?

Best,

Miguel

During the ESD indirect discharge +-15K test, it was found that the FPD-linK III signal was interfered, resulting in screen flickering; ESD devices were added to the interfaces. As shown in the following figure, the closer to the serialized ds90ub949A-Q1, the higher the probability of screen flickering.

Hi,

Thanks for providing.

A good indication of where the ESD test is affecting the end-to-end video is by first checking the LOCK status of the FPD-Link devices. A stable lock during the ESD test will indicate that the link is stable and not affected, but that the problem might reside with the Open LDI (LVDS) output.

You can monitor the LOCK status over the link between the SER and the DES by checking 948's pin 1 to see if it dips low during this ESD test.

If this is identified, we can pinpoint which part of the system would require improvement.

Some other considerations include where the ESD is injected, on the connector housing, or directly to the trace? Also, the housing should be considered and return ground paths to the PCB board itself.

Please identify the LOCK status during the test on the device.

Best,

Miguel