User's Guide

UL865 Hardware User Guide

1VV0301050 Rev 2 – 2013-10-09

The UL865 includes one integrated universal serial bus (USB) transceiver:

This port is compliant with the USB 2.0 HS only.

The following table is listing the available signals:

PAD

Signal

I/O

Function

Type

NOTE

USB_D+

I/O

USB differential Data (+)

3.3V

USB_D-

I/O

USB differential Data (-)

3.3V

VUSB

Power sense for the internal USB

transceiver.

Accepted range:

4.4V to 5.25V

The USB_DPLUS and USB_DMINUS signals have a clock rate of 480 MHz. The signal

traces should be routed carefully. Trace lengths, number of vias and capacitive

loading should be minimized. The impedance value should be as close as possible to 90

Ohms differential.

NOTE:

VUSB pin should be disconnected before activating the Power Saving Mode.

The USB 1.1 mode could be used to provide AT Commands / Data communication but not

for a SW upgrade.