STMicroelectronics STUSB03EDEMOBO

Overview

STUSB03EDEMOBO from STMicroelectronics is a USB 2.0 full-speed/low-speed transceiver evaluation board built around the STUSB03E QFN16 transceiver IC. It supports 12 Mbps and 1.5 Mbps operation, integrates a 3.3 V LDO, features ±14 kV HBM ESD protection on D+/D–, and enables software-controlled re-enumeration for portable systems including MP3 players and mobile phones.

For engineers reviewing the STUSB03EDEMOBO datasheet, STUSB03EDEMOBO pinout, STUSB03EDEMOBO application, or STUSB03EDEMOBO equivalent, this page provides verified functional context, key interface specifications, supply domain isolation details, suspend-mode current behavior, and evaluation-ready configuration guidance for USB physical layer integration.

Technical Context

The STUSB03EDEMOBO implements the STUSB03E transceiver in a fully configured evaluation layout, with dedicated VBUS (4–5.5 V), VIF (1.6–3.6 V), and VTRM (3.3 V) supply domains. It exposes all control pins - SPD, RSEL, CON, OE#, SUS - enabling hardware- and software-driven speed selection, pull-up resistor activation, and suspend mode entry.

It demonstrates sharing mode operation when VBUS is absent, allowing D+/D– lines to be multiplexed with other serial protocols. The board includes decoupling capacitors per datasheet requirements (e.g., 1.0 µF on VTRM), VBUS detection circuitry, and configurable pull-up termination via VPU output (3.3 V ±10%) for both full-speed and low-speed USB enumeration.

Key Specifications

Availability

STUSB03EDEMOBO is available at Aetrix Electronics and suitable for USB peripheral development, embedded device bring-up, and low-power mobile interface validation requiring stable component supply, traceable sourcing, and lifecycle continuity.

Supply support for STUSB03EDEMOBO includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, analog ICs, power management devices, and USB interface solutions for industrial, automotive, and consumer markets.

The STUSB03E product line delivers USB 2.0 physical layer transceivers optimized for battery-powered portable electronics, emphasizing ultra-low suspend current, dual-speed compatibility, and seamless integration with sub-3.6 V system I/O rails.

FAQ

Does STUSB03EDEMOBO support USB enumeration without external pull-up resistors?

Yes. The STUSB03EDEMOBO leverages the onboard STUSB03E's integrated 1.3 kΩ D+ pull-up resistor, enabled by default when SPD = HIGH and RSEL = HIGH. External resistors are only required if RSEL is tied LOW, in which case the VPU pin supplies 3.3 V to drive an external 1.5 kΩ resistor between VPU and D+ for full-speed mode.

Can STUSB03EDEMOBO operate with a 1.8 V system I/O supply?

Yes. The STUSB03E on the demo board accepts VIF from 1.6 V to 3.6 V, making it compatible with 1.8 V microcontroller I/O interfaces. All digital control pins (SPD, RSEL, CON, OE#, SUS) and RCV output are referenced to VIF, ensuring correct logic thresholds and signal integrity at 1.8 V.

How does STUSB03EDEMOBO handle VBUS absence during system operation?

When VBUS is disconnected, the STUSB03E enters Sharing Mode: D+/D– lines go high-impedance, VPU becomes high-Z, and VBUSDET goes LOW. This allows the same differential pair to be reused for alternate protocols (e.g., UART or I²C) without signal contention or leakage paths, as confirmed in the functional tables and Figure 3 of the datasheet.

What is the purpose of the VTRM pin on STUSB03EDEMOBO?

VTRM is the 3.3 V reference output from the integrated LDO, used to bias the transceiver's analog front-end and provide stable termination voltage. On STUSB03EDEMOBO, it is externally decoupled with a 1.0 µF capacitor (per datasheet requirement) to ensure stability under dynamic USB signaling loads and prevent supply droop during data transitions.