General Description
The MAX3420E contains the digital logic and analog circuitry necessary to implement a full-speed USB peripheral compliant to USB specification rev 2.0. A builtin full-speed transceiver features ±15kV ESD protection and programmable USB connect and disconnect. An internal serial-interface engine (SIE) handles low-level USB protocol details such as error checking and bus retries. The MAX3420E operates using a register set accessed by an SPI interface that operates up to 26MHz. Any SPI master (microprocessor, ASIC, DSP, etc.) can add USB functionality using the simple 3- or 4-wire SPI interface.

Benefits and Features
● Simplifies Adding USB to Any System
    • Microprocessor-Independent USB Solution
    • Complies with USB Specification Revision 2.0 (Full-Speed Operation)
    • Integrated Full-Speed USB Transceiver
    • Firmware/Hardware Control of an Internal D+ Pullup Resistor
    • Programmable 3 or 4-Wire 26MHz SPI Interface
    • Intelligent USB Serial-Interface Engine (SIE)
    • Automatically Handles USB Flow Control and Double Buffering
    • Handles Low-Level USB Signaling Details
    • Includes Timers for USB Time-Sensitive Operations, So SPI Master Does Not Need to Time Events
    • Four General-Purpose Inputs and Four GeneralPurpose Outputs
● Internal Comparator Detects VBUS for Self-Powered Applications
● Interrupt Output Pin (Level or Programmable Edge) Allows Polled or Interrupt-Driven SPI Interface
● Double-Buffered Data Endpoints Increase Throughput by Allowing the SPI Master to Transfer Data Concurrently with USB Transfers Over the Same Endpoint
    • Built-In Endpoint FIFOs
    • EP0: CONTROL (64 Bytes)
    • EP1: OUT, Bulk or Interrupt, 2 x 64 Bytes (Double-Buffered)
    • EP2: IN, Bulk or Interrupt, 2 x 64 Bytes (Double-Buffered)
    • EP3: IN, Bulk or Interrupt (64 Bytes)
● SETUP Data Has Its Own 8-Byte FIFO, Simplifying Firmware
● ESD Protection on D+, D-, and VBCOMP Improves System Reliability

Applications
● Cell Phones
● PC Peripherals
● Microprocessors and DSPs
● Custom USB Devices
● Cameras
● Desktop Routers
● PLCs
● Set-Top Boxes
● PDAs
● MP3 Players
● Instrumentation