Issue in CX3 SPI booting at 1.8V level

[Anonymous]

Hi

   

We made custom board with CYUSB3065-BZXC controller and used "W25Q80EW" flash for SPI boot support. Our board is functional at 1.8V I/O level and we are not able to boot over SPI flash now.

   

For reference we checked the same in Cypress EZ-USB CX3 MIPI CSI-2 to SuperSpeed USB controller RDK with hardware modification for 1.8V I/O and External SPI flash(W25Q80EW). But we are facing same issue in RDK also. However the SPI boot works fine at 3.3V level.

   

Any body has faced issue in CX3 SPI booting at 1.8V level ?

   

Kindly help.

       

Regards

   

Pandiyarajan

[Anonymous]

Hi,

   

Have you set the VIO4 voltage levels also as 1.8V (The power domain that supports SPI Block).

   

In please check if there is any noice over the SPI Lines (which might dominate the actual data signals at 1.8V)

   

Regards,

   

-Madhu

[Anonymous]

Hi ,

   

Yes the VIO4 is connected to 1.8V only. Now we found a workaround with pulldown for MISO line which is allowing us to boot over SPI flash. Can you please elaborate on the noise over SPI line & its threshold (if any) ?  Are you mentioning about power noise VIO4 ?

   

Thanks

   

Pandiyarajan

[Anonymous]

Yes, I was mentioning about the power noise of VIO4.

   

Regards,

   

- Madhu Sudhan