3 Replies Latest reply on Feb 21, 2019 11:11 PM by KandlaguntaR_36

    CX3 ESD FAILURE

    sana_2282546

      Hi,

      I have designed a board with CX3 chip ( CYUSB3065-BZXI ) and deployed for ESD testing with the below configuration, during the ESD test CX3 chip gets restart. Even though the ESD standard accepts if the device gets recovered from the ESD spikes ( performance criterion B ), I would like to have my device to get pass in criterion A in ESD testing ( immune to ESD spike and continues to function normally without any compromise ). Can you please let me know how to get pass ESD test with performance criterion A or is this the behaviour of the CX3 chip in ESD environment. Do please clarify me on this.

       

      Tested scenario:

      1) Connected custom made board with CX3 chip to a laptop via USB 3.0 cable ( 1meter length )

      2) Have programmed CX3 such that it gives dummy MIPI data via USB. The frames ( 180 fps ) were viewed in laptop through custom made application

      3) Have provided ESD voltages of  +/- 2kV , 4kV, 6kV and 8kV in contact discharge ( both direct and indirect method ) and till +/- 15kV in air discharge ( on the USB cable )

      4) Have provided ESD diode to USB 2.0 line, USB 3.0 SS pair and VBUS

      5) In the above condition CX3 gets reset and frame rate gets stop ( 0 fps )

       

      I just want to receive the frames seamlessly without any disruption while performing ESD test

       

      Thanks in advance

      Sathiya

        • 1. Re: CX3 ESD FAILURE
          KandlaguntaR_36

          Hello Sathiya,

           

          We have helped a few customers to pass the ESD test with Criteria B and some customers reported that they have passed the ESD test criteria A.

           

          If you couldn't get the test pass with Criteria A, please go with Criteria B. You may use a timer so that when there is no data streaming (DMA activity), the timer expires and reset the DMA channels. This will resume video streaming.

           

          Please refer OV5640 example firmware for the timer implementation - C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\firmware\cx3_examples\cycx3_uvc_ov5640

          • 2. Re: CX3 ESD FAILURE
            sana_2282546

            Hi Kandlagunta,

             

            Thanks for your reply, In the CX3 chip datasheet it is mentioned under the System-level ESD topic as,

            " ±6-kV contact discharge and ±8-kV air gap discharge based

            on IEC61000-4-2 level 3A using external system-level

            protection devices

             

            ± 8-kV contact discharge and ±15-kV air gap discharge based

            on IEC61000-4-2 level 4C using external system-level

            protection devices "

             

            can you please explain me what does level 3A and level 4C referes to?

            • 3. Re: CX3 ESD FAILURE
              KandlaguntaR_36

              Sathiya,

               

              Level 3 and Level 4 are test levels and A and C are performace criteria as per IEC 61000-4-2.

               

              The following are the IEC 61000-4-2 Test Levels:

               

              Contact Discharge

              Air Discharge

              Level

              Test Voltage (kV)

              Level

              Test Voltage (kV)

              1

              2

              1

              2

              2

              4

              2

              4

              3

              6

              3

              8

              4

              8

              4

              15

               

              Here are various performace criteria:

               

              A     - Normal Performance within limits specified by the manufacturer, requestor or purchaser

              B     - Temporary loss of function or degradation of performace which ceases after the distrubance ceases, and from which the equipment under test recovers its normal performace, without operator intervention

              C    - Temporary loss of function or degradation of performace, the correction of which requires operator intervention

              D    - Loss of function or degradation of performace which is not recoverable, owning to damage to hardware or software, or loss of data