NI USB-8451 I2C/SPI/SMBus Interface

  • Print
  • PDF
  • Rich Text
  • Bus-powered USB interface for I2C, SMBus, and SPI communication; cable included
  • Compatible with Windows 7/Vista/XP/2000
  • I2C master interface with clock rates up to 250 kHz
  • SMBus master interface with clock rates up to
    100 kHz
  • SPI master interface with clock rates up to 12 MHz
  • High-level API for NI LabVIEW, NI LabWindows™/CVI, and Microsoft Visual C/C++ 6.0
  • Available in OEM board-only version
  • 8 general-purpose digital I/O lines
  • Data Sheet
  • View Support Resources
The NI USB-8451 is an interface for connecting to and communicating with I2C, SMBus, and SPI devices. With plug-and-play USB connectivity, the USB-8451 is a portable solution to communicate with consumer electronics and integrated circuits. It also includes eight general-purpose digital I/O lines for a variety of applications, such as configuring the address of I2C devices or toggling LEDs.

The USB-8451 can be physically located more closely to I2C/SPI devices than PCI interfaces, reducing I2C bus length and minimizing noise problems. Additionally, the interface provides
+5 V and GND to power circuits up to 230 mA with no external power supply.

The NI USB-6000 prototyping accessory attaches to the 16-position connector of the USB-8451 (non-OEM version) interface. It has a small breadboarding area for custom-defined signal conditioning and prototyping within the housing. You can use up to two accessories per USB-8451 module.

The mark LabWindows is used under a license from Microsoft Corporation. Windows is a registered trademark of Microsoft Corporation in the United States and other countries.

Data Sheet | View Pricing and Purchasing Information

Specifications Documents

  • Data Sheet

Specifications Summary

Part Number Description Est Ship  US Dollars Qty
I2C and SPI Interface
779553-01USB-8451, I2C/SPI/SMBus Interface1 - 3$ 446.00
779553-50USB-8451, I2C/SPI/SMBus Interface, Board Only OEM Version5 - 10$ 414.00
Related Products and Accessories
779511-01NI USB-600x Series Prototyping Accessory5 - 10$ 37.00

Guarantee your price for 30 days (learn more)

Instant Quote

Extended Warranties

National Instruments designs and manufactures all products to minimize failures, however unexpected failures can still occur. Extended warranties provide a fixed economical price at the time of system purchase, covering any repair costs for up to three years. In addition, they offer the following benefits:

  • Significant cost savings compared to individual repair incidents
  • Fault location, diagnostics, and repair by NI any time the system product fails
  • All parts and labor costs covered as well as any adjustments needed to restore the hardware to manufacturing specifications

For more information about your warranty options:


NI recognizes the need to maintain properly calibrated devices for high-accuracy measurements. NI provides manual calibration procedures, services to recalibrate your products, and automated calibration software to calibrate many NI measurement products.


NI training is the fastest, most certain route to productivity with NI tools and successful application development.

Repair Services

Return your registered product under warranty at no additional labor and parts cost. NI offers fault location, diagnostics, and repair any time the system fails as well as any adjustments needed to restore the hardware to manufacturing specifications.

Technical Support

Additional Product Information

  • Data Sheet