Custom LPC11U35 dev board - Device Descriptor Request failed w/ MSC bootloader

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by twiddle on Sat Feb 28 16:20:26 MST 2015
So I've put together a simple dev board intended for USB use and modelled after the schematics in the datasheet as well as the "ARM Pro Mini" project.
However, I don't appear to be getting any response out of the chip, when I connect the device to USB.
I get "Device Descriptor Request failed" from my Win8 machine, which I suspect is due to the fact, as per the datasheet's suggestion for a bus powered device, I've connected a pullup directly between USB_DP and 3V3 directly rather than using USB_CONNECT, so my computer is seeing an attached device regardless of whether the chip is actually initializing properly. USBView shows nothing being received for the device descriptor at all, which leads me to think that my chip is not functional at all.
Bearing this in mind I am posting my schematic/layout in case I've got some rudimentary error in my design, in the hopes I can get some insight into what I'm doing wrong.
Any input would be appreciated! Thanks.

Here's the layout (schematic attached below as PDF):