STUSB02E datasheet(15/20 Pages) STMICROELECTRONICS

15 / 20 page

STUSB02E

Functional description

15/20

Functional description

The STUSB02E is designed to provide USB connectivity in mobile systems where available system

supply voltages are not able to satisfy USB requirements. The STUSB02E can operate down to supply

voltages of 1.6V. As shown in the circuit above, the STUSB02E takes advantage of the USB supply

voltage, VBUS, to operate the transceiver. The system voltage, VIF, is used to set the reference voltage

used by the digital I/O lines interfacing to the system controller. Internal circuitry provides translation

between the USB and system voltage domains. VIF will typically be the main supply voltage rail for the

controller.

In addition, a 3.3V, 10% termination supply voltage, VPU, is provided to support speed selection. VPU can

be disabled or enabled under software control via the CON input. This allows for software-controlled

connect or disconnect states. A 1.5K

Ωresistor is required to be connected between this pin and the D+ or

D– lines to respectively specify full speed or low speed operation.

The use of ESD transient protection devices is not required for operation, but is recommended.

STUSB02E Datasheet(PDF) 15 Page - STMicroelectronics