EZUSB

EZ-USB is a family of USB peripheral controllers developed by Cypress Semiconductor (originally Anchor Chips) that enables devices to implement USB functionality with integrated hardware support. The devices combine a USB transceiver, a processor core, on‑chip RAM, and a programmable data path, allowing designers to create custom USB endpoints and data flows without a separate host controller.

A central feature across the EZ-USB line is the General Programmable Interface (GPIF), particularly GPIF II, which provides a configurable data path that can connect USB endpoints to external memory or logic. The architecture typically includes a DMA engine to move data between USB endpoints, on‑chip memory, and external interfaces, enabling high‑throughput data streaming. Depending on the model, the devices may also include multiple endpoints, packet buffering, and various power-management options.

Early EZ-USB parts such as FX1 and FX2/FX2LP used an 8051‑compatible microcontroller core and supported USB full‑speed or high‑speed operation. The FX2 family popularized flexible data paths and robust development tools, while the FX2LP offered lower power consumption. Later generations, such as the FX3 family, provided higher bandwidth and more modern processing capabilities to support USB 3.0 while maintaining the EZ‑USB design philosophy of offloading USB protocol handling from the host.

Developers use Cypress toolchains to program the on‑chip core and configure GPIF II, often describing data paths graphically or via state machines. This enables custom USB devices that can implement proprietary protocols while leveraging hardware USB handling.

EZ-USB devices have seen wide use in multimedia adapters, audio interfaces, card readers, and other USB peripherals. Since Cypress’s acquisition by Infineon, the line has evolved, with FX3 and related products representing newer high‑speed options, while the legacy EZ‑USB devices remain in historical and some niche deployments.