iMX537 issues

[chiranjeevimata]

Hi All,

I am using iMX537 in my target board and finding peculiar problem while programming. In my target board whenever i am trying to program, iMX537 doesnt responds to the JTAG connectivity.

On doubting the BGA soldering, i pressed the BGA it started responding. Then i tried to reduce my contact pressure on the chip still it works. Later i tried on other 2 target boards found the similar behavior. There after i concluded that its not soldering issues. Even a simple touch will make the iMX537 to respond. One observation that i did was when ever i turn on the power to the board initially target board consumes 250mA @ 8.4V. Later when i touch the iMX537 the current consumption changes to 300mA @ 8.4V , It starts responding to JTAG even though i am not touching.

Please suggest me solutions if someone has faced similar sort of issue in there design or is it any peculiar behavior of some iMX537 batch.

Regards,

Chiru

[b36401]

Actually we never met similar issues before.

I only can suspect that there is something wrong with the power
scheme or with processor power-up seqence. So the processor
does not start when you turned the power on and when you touch
the processor this small electric discharge stars the system up.

As for sample bring-up checklist for the board please refer
chapter 7 of i.MX53 System Development User's Guide.
You can perform the tasks listed in the table 7-2
with and without finger. If you see some difference you
get an idea what exactly is going wrong.

[chiranjeevimata]

Hi Victor,

We are using DA9053-3N for power sequencing. I checked the power up sequencing its meeting as per the Pageno112 of iMX53UG.pdf.

Also as mentioned in the earlier post, the only change that i found is that the board power consumption changes from 240mA to 270mA after touching.

I have one doubt, Initially the JTAG_MODE was pulled up to 3.3V, when it was not getting detected i changed the pull-up to pull-down then JTAG started detecting only when i touch the processor.

Please let me know will JTAG_MODE pin will cause any problem.

Regards,

Chiranjeevi M