I have a problem. I worked on LPC4337 device powered by the USB bus. Power 3.3V produces a dc-dc converter TPS62067. Used Peripherals - USB interface, SPI and SPIFI (connected 2 SD card). Made a few dozen devices. With a fairly frequent use of the controllers have begun to fail. Namely, when the USB connection to the PC terminal.
I find out what goes down USB0 power domain. This domain power punches and it has a short to ground GND. Power supply to the domain through contacts and USB0_VDDA3V_DRIVER USB0_VDDA3V3. Used circuit according LPC1830_Xplorer_schematic.pdf. And if I disconnect the power from the domain of USB (desoldering ferrite), the core and the periphery of the controller function with the exception of USB interface.
What could be the reason?