Microchip Technology USB2642T/ML

Overview

USB2642T/ML from Microchip Technology is a USB 2.0-compliant, single-chip hi-speed hub and flash media controller combo IC. It integrates a 2-port downstream USB 2.0 hub with an embedded SD/MMC/eMMC card reader (exposed as a compound device on port #3), supports I²C-over-USB bridging, delivers sustained flash transfer rates >35 MB/s, and operates across industrial temperature range (–40 °C to +85 °C). It is used in desktop docking stations, A/V monitors, and multi-format card readers.

For engineers reviewing the USB2642T/ML datasheet, USB2642T/ML pinout, USB2642T/ML application, or USB2642T/ML equivalent, key selection considerations include its dual-role architecture (hub + media controller), programmable PortSwap/PHYBoost features for PCB layout flexibility, internal/external firmware configuration via SPI, and support for SDXC/eMMC up to 2 TB addressability.

Technical Context

The USB2642T/ML implements a shared Transaction Translator (TT) for both downstream ports, enabling concurrent full-speed and low-speed peripheral operation. Its integrated 8051-based processor manages hub control, SD/MMC protocol translation, and I²C bridge command execution via SCSI pass-through over Mass Storage Class.

It uses a single 24 MHz crystal for clock generation, supports internal 1.8 V core regulation (via REG_EN), and embeds all USB termination and pull-up/down resistors. The flash interface connects directly to SD_D[7:0], SD_CMD, SD_CLK, SD_nCD, and SD_WP pins with dedicated CRD_PWR (200 mA) drive capability.

Key Specifications

Pinout & Package

USB2642T/ML is housed in a 48-pin QFN package (7 mm × 7 mm, 0.5 mm pitch) with exposed thermal pad (ePad) requiring connection to ground via multiple vias. All power pins (VDD33, VDDA33, VDD18, VDD18PLL) require specified bypass capacitors (1.0 µF or 4.7 µF).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB hub and flash media controller applications.

Compared with USB2642T/ML, USB2514B-AIZM offers higher port count but requires external components for media functionality, while GL827L-16 provides basic combo capability without industrial temp rating, SDXC/eMMC support, or signal integrity enhancements-making USB2642T/ML the only option meeting full specification compliance, programmability, and extended storage requirements.

Availability

USB2642T/ML is available at Aetrix Electronics and suitable for desktop docking stations, smart monitors, and industrial media players requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for USB2642T/ML 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

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and USB connectivity solutions, headquartered in Chandler, Arizona.

USB2642T/ML belongs to Microchip's USB Hub and Combo Controller product line, designed specifically for space-constrained, multi-interface peripheral applications requiring integrated USB expansion and flash media access.

FAQ

What is the primary function of the USB2642T/ML?

The USB2642T/ML is a single-chip USB 2.0 hi-speed hub and flash media controller combo IC. It integrates a 2-port downstream USB hub, an SD/MMC/eMMC card reader (exposed as a compound USB device), and an I²C-over-USB bridge. Its design consolidates three functions into one RoHS-compliant 48-pin QFN package, reducing system complexity and board space. USB2642T/ML enables seamless media ingestion and peripheral expansion in consumer and industrial USB hosts.

Does USB2642T/ML support SDXC and eMMC cards?

Yes, USB2642T/ML fully supports SDXC and eMMC devices per Secure Digital 2.0 and MultiMediaCard 4.2 specifications. It enables storage addressability up to 2 TB and handles SDHC, SDXC, microSD, and embedded MMC formats-including 1/4/8-bit bus modes. The SD_D[7:0], SD_CMD, SD_CLK, SD_nCD, and SD_WP pins provide direct hardware interface, and CRD_PWR supplies 200 mA at 3.3 V to the card slot. USB2642T/ML validates compatibility through built-in protocol translation and timing control.

How does the PortSwap feature benefit PCB layout?

PortSwap allows programmable reassignment of USB differential-pair pin locations (e.g., swapping USBDN_DP2/DM2 to alternate pins), enabling direct alignment of D+/D– traces to physical USB connectors without crossing or length mismatch. This preserves signal integrity and simplifies routing in dense layouts. USB2642T/ML implements PortSwap via configuration registers loaded from SPI ROM or internal default firmware-eliminating manual trace revisions across platform variants.

Can USB2642T/ML operate without an external crystal?

No-USB2642T/ML requires a 24 MHz timing reference, either from a 24 MHz crystal connected between XTAL1 and XTAL2, or from an external 24 MHz clock source applied to XTAL1 (with XTAL2 left unconnected). The PLL and USB data recovery circuitry depend on this precise frequency; deviation causes USB enumeration failure or data corruption. USB2642T/ML does not support internal RC oscillators or alternative clock sources.

What power supply configurations does USB2642T/ML support?

USB2642T/ML supports both internally and externally regulated 1.8 V core operation. When REG_EN is high (default), internal regulators generate 1.8 V for VDD18 and VDD18PLL; external 1.8 V supplies must be disconnected except for bypass capacitors. When REG_EN is pulled low, external 1.8 V sources must power VDD18 and VDD18PLL directly. VDD33 (3.3 V) and VDDA33 (3.3 V analog) are always supplied externally. USB2642T/ML includes dedicated bypass capacitor requirements per pin (e.g., 4.7 µF on VDDA33 pin 48).