iMx28 power rail voltage problem

ashutosh · ‎08-09-2018

We have designed a board using iMx28. Two boards are fabricated, assembled & working fine.

Now, our plan is to go for production. Before that we got another 2 boards assembled.

But, in these boards, not getting processor voltages properly.

Getting 0.7v for 3.3v & 0.9v for 1.8v.

What can be the reason?

We are having very less time to meet the schedules.

Pl help us to resolve the issue ASAP.

Thank You

weidong_sun · ‎08-10-2018

The current situation you are facing is :

(1) Two boards are working fine, no any problem.

(2) Another 2 boards with the same design as above, but they don't normally work. Getting 0.7v for 3.3v & 0.9v for 1.8v. RIGHT?

If yes, my advice is :

(1) check if there exists on SMT.

(2) measuring volatge of PSWITCH pin. The pin's voltage will determine if DC-DC converter starts up. see below, please!

Have a nice day!

Best Regards,

Weidong Sun