MAX3349EEBE+T

Overview

The MAX3349EEBE+T is a USB transceiver with UART multiplexing mode, designed for full-speed (12Mbps) USB 2.0 interfaces. It operates from a VBUS supply of 3.0V to 5.5V and supports a logic voltage (VL) range of 1.40V to 2.75V. The device features ±15kV ESD protection on D+/D- pins and includes an internal linear regulator generating VTRM. In UART mode, it accepts a separate VUART input between 2.7V and 3.3V, supporting baud rates up to 921kbps. It is housed in a 16-bump UCSP package and functions within an operating temperature range of -40°C to +85°C.

Feature Summary

• Supports dual-mode operation allowing seamless switching between USB signaling and external UART routing through a shared connector.
• Integrates an internal linear regulator to derive power directly from the USB cable without requiring external sequencing.
• Provides robust electrostatic discharge protection rated at ±15kV Human Body Model on differential data lines.

Applications

• Mobile cellular phones
• Personal Digital Assistants (PDAs)
• Digital cameras

Procurement Notes

Verify the component matches the specific 16-bump UCSP package configuration. Confirm that the ordering suffix indicates lead-free and RoHS compliance as specified in the manufacturer's documentation. Ensure the part number corresponds to the extended temperature range variant required for the target application environment.

Selection Notes

Select this component when a single connector must support both USB host connectivity and legacy UART communication to reduce board space. Ensure the system design accommodates the separate VUART supply requirement if UART mode functionality is needed. Verify that the low-voltage logic interface aligns with the ASIC or microprocessor operating voltages.

Part Context

This device belongs to the MAX3349E series of high-speed USB transceivers. It is specifically engineered for mobile applications where cost and part count reduction are critical. The UCSP package offers a compact footprint suitable for space-constrained portable electronics compared to larger surface-mount packages.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Direct replacement requires verification of pin compatibility and electrical specifications against the original design requirements.

FAQ

How does the device switch between USB and UART modes?

The device automatically switches modes based on the presence of VBUS. When VBUS exceeds the detection threshold, BD goes high and the device enters USB mode. If VBUS is absent, BD goes low, and the device operates in UART mode.

What is the function of the ENUM pin?

The ENUM pin controls the internal 1.5kΩ pullup resistor on the D+ line. Driving ENUM high connects the resistor to allow logical connection to the USB bus, while driving it low disconnects the resistor for logical disconnection.

Can the MAX3349EEBE+T be powered directly from a USB port?

Yes, the device features an internal linear regulator that allows direct powering from the USB cable via the VBUS pin, eliminating the need for external power sequencing.