AnsweredAssumed Answered

BF527 Low Ohm Short

Question asked by seddona on Oct 25, 2010
Latest reply on Nov 9, 2010 by JoeT

We are currently experiencing an issue with our custom BF524BBCZ-4A based board where VDDRTC or USBVDD both powered by the 3.3V rail develop a short to ground over time. We have 3 prototype boards, the three different shorts are 40, 90 and 400 ohms . I am unable to isolate VDDRTC from USBVDD at the moment so I can't be 100% sure which supply is at fault. Both of the peripherals function fine on these boards but the short causes the hibernate current to be much larger than it should be. A few questions;


1. Is this a known failure mode or something that anybody has seen before?


2. Our board fairly closely follows the BF526-EZBRD and thus does not have any power supply sequencing, the datasheet indicates that this is not an issue?