topic failed DDR DQS Auto calibration-LPC3250 in LPC Microcontrollers

failed DDR DQS Auto calibration-LPC3250

justinvil1103 — Thu, 26 Jan 2023 19:51:31 GMT

Hi,

We are running a DDR test and the following feature of the LPC3250 "DDR DQS Auto calibration" kept failing. We do not know what cause it to fail, any help would be greatly appreciated.

Thanks,

Re: failed DDR DQS Auto calibration-LPC3250

vicentegomez — Fri, 27 Jan 2023 23:36:43 GMT

Normally the DDR problems are due to hardware issues,

Do all the lines have the same impedance?

there are some application notes with recommendations about DDRs

https://www.nxp.com/docs/en/application-note/AN10935.pdf

I hope this will help you.

Re: failed DDR DQS Auto calibration-LPC3250

justinvil1103 — Tue, 31 Jan 2023 19:03:42 GMT

Hi Vicente,

We have a one-time calibration at boot up, what would happen if we turn the "Auto Calibration" off? or disable it?

Thanks, WJ