NI USB-8451 I2C/SPI/SMBus Interface

  • 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
  • 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.

Specifications Documents

  • View Data Sheet

Specifications Summary


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Part Number Description Est Ship Blue Diamond US Dollars Qty
I2C and SPI Interface
779553-01USB-8451, I2C/SPI/SMBus Interface2 - 5$ 455.00
779553-50USB-8451, I2C/SPI/SMBus Interface, Board Only OEM Version10 - 15$ 422.00

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