USB-8451 Overview

The NI USB‑8451 is a bus‑powered USB interface device for I²C, SMBus, and SPI communication, designed primarily for engineers and embedded systems developers. Use the NI USB‑8451 to quickly prototype, test, and communicate with integrated circuits such as sensors, ADCs, EEPROMs, and other consumer‑electronics components.

The NI USB-8451 is available in an enclosure and as a board-only version. In this manual, the enclosure version is referred to as the NI USB-8451, and the board-only version is referred to as the NI USB-8451 OEM. Unless otherwise noted, all information in this manual applies to both the NIUSB-8451 and NI USB-8451 OEM.

USB-8451 Key Features

The NI USB-8451 has the following features and capabilities.

  • Dual‑protocol master interface (I²C + SPI) – Communicate with a wide range of embedded devices using built‑in I²C, SMBus, and SPI master interfaces.
  • Plug‑and‑play USB connectivity – Bus‑powered, full‑speed USB interface enables easy setup and portable use close to target devices.
  • 8 general‑purpose digital I/O lines – Configure device pins, toggle LEDs, or support custom test interactions. Each DIO line can be set as input or output.
  • Ideal for testing and programming ICs – Commonly used with sensors, ADCs, EEPROMs, microcontrollers, and other consumer‑electronics components.
  • High‑level LabVIEW API support – Provides an easy‑to‑use development experience with both basic and advanced scripting APIs for custom transactions.
  • Portable, close‑to‑device operation – Designed to be placed near I²C/SPI devices to reduce bus length and noise issues, improving signal reliability.
  • Onboard +5 V power output – Supplies power to small circuits without requiring an external supply.
  • Supports multiple addressing and modes. Includes 7‑bit and 10‑bit I²C addressing and multiple SPI modes for flexibility across device types.