LPC43S70 Revision D can not run and be connected to debug by SWD

[kevinllc]

Hello,

I got a condiction.Our product use the LPC43S70FET256,the flashless part,with a flash chip 25Q800.

The device revision 'A' 'C' 'F' of LPC43S70FET256 works well without any issue,but one of the production batch we used 15pcs of revision 'D' and 5pcs of revison 'F',the PCBs and components are same.All the 'D' can not work at all,but all the 'F' work well .We found that,the PCB with the revision 'D' ,could not be programed or debug from the SWD interface,the error log is "connection fail".And we replace the flash chip 25Q800 in PCB with revision 'D'(the flash chip datas are blank,because we could not programed from the SWD yet),with a pre-programed functional one,and found that the PCB still can not work.And we have check the nReset signal,it is good.

All the PCBs and components are same,except the revision of LPC43S70FET256.That is a very strange issue.We had check the Errata sheet and could not found anything useful.

Did anyone have the same issue before?Thank you for any reply!

[kevinllc]

Hi Jun Zhang

Thank you for your reply.

[ZhangJennie]

Hi kevinllc 

I checked errata. there is no known record only for rev D. 

https://www.nxp.com.cn/docs/en/errata/ES_LPC43SX0.pdf

Where did you purchase revD from? If from NXP official distributor, I suggest you contact them to start a failure analysis.

Thanks,

Jun Zhang