Lattice HW-USBN-2A: A Comprehensive Technical Overview and Application Guide

The Lattice HW-USBN-2A represents a cornerstone technology in the realm of hardware-based USB connectivity solutions. As a dedicated USB interface controller, it provides a robust and flexible bridge between a host system and programmable logic, typically a Field-Programmable Gate Array (FPGA). This device is engineered to handle the complexities of the USB 2.0 protocol, offloading this task from the main logic and enabling developers to focus on their core application functionality.

Technical Architecture and Core Features

At its heart, the HW-USBN-2A is designed for high-performance and ease of integration. Its architecture is built around a dedicated USB 2.0 transceiver (PHY) and a serial interface engine (SIE). The integrated PHY supports both full-speed (12 Mbps) and high-speed (480 Mbps) data rates, ensuring compatibility with a vast array of peripherals and host controllers. The SIE is responsible for the low-level packetization, error checking, and handshaking required by the USB protocol, which significantly reduces the design burden on the connected FPGA.

A key feature of this controller is its configurable parallel interface. This interface allows for seamless connection to an FPGA, acting as a conduit for data and control signals. The bus width and timing are often configurable, providing design flexibility to match the performance requirements and resource availability of the target FPGA. Furthermore, the controller manages essential USB functions such as enumeration, endpoint management, and power management (including Suspend/Resume states), ensuring full compliance with the USB specification.

Application Guide and Implementation

The primary application of the Lattice HW-USBN-2A is to add USB 2.0 capability to systems centered on an FPGA. A typical implementation flow involves several key steps:

1. Hardware Integration: The controller is mounted on a PCB with its connections to the FPGA's I/O pins and a standard USB connector. Careful attention must be paid to the USB signal integrity guidelines for high-speed operation, including controlled impedance routing and proper termination.

2. FPGA Logic Design: Within the FPGA, a logic block (often provided as Intellectual Property (IP) by Lattice) is implemented. This IP core communicates with the HW-USBN-2A over the parallel interface. It typically presents a simpler, FIFO-based interface to the user logic inside the FPGA, abstracting away the complexities of the USB protocol.

3. Firmware and Software Development: On the host computer (e.g., a PC), a device driver is required. This can be a custom driver or a standard class driver (like CDC or HID) depending on the application. The driver facilitates communication between the host operating system and the device. Simultaneously, the FPGA's user logic is designed to read from and write to the IP core's data FIFOs to exchange application-specific data with the host.

This solution is ideal for a wide range of applications, including data acquisition systems, where sensors stream data to a PC for analysis; industrial control interfaces, providing a reliable communication link for configuring machinery; and prototyping and development, allowing for rapid iteration of ideas that require a high-speed PC connection.

ICGOOODFIND

The Lattice HW-USBN-2A is a highly integrated and reliable solution that simplifies the complex task of adding high-speed USB 2.0 connectivity to FPGA-based designs. Its combination of a hardened PHY, a dedicated SIE, and a flexible parallel interface makes it an indispensable component for engineers, streamlining development and ensuring robust performance across diverse industrial and commercial applications.

Keywords:

USB 2.0 Controller

FPGA Interface

Hardware Integration

Serial Interface Engine (SIE)

Data Acquisition