AnsweredAssumed Answered

BF524 USB block power

Question asked by Mack on Feb 11, 2014
Latest reply on Feb 19, 2014 by matchaze

Hello,

 

My board was designed with BF524. BF524 operates as USB device. The circuit is coped below and the same as evaluation B/D.

Occasionally, the following situation happens while operating.

- VBUS from usb host keeps supplied to USBVBUS of BF524 although board power(USBVDD1 and USBVDD2) is off.

 

After the situation, USB block of BF524 seems to become defective(broken). I wonder if BF524 USB block is possibly defective when USBVBUS is powered and USBVDDx is not powered. So should I revise my hardware to avoid the situation?

BF524 USB.PNG

Best Regards,

Mack

Outcomes