3.3 MHz I2C, 50 MHz SPI I2C/SPI Interface Device—The NI USB‑8452 is a master interface for connecting to and communicating with inter-integrated circuit (I2C) and serial peripheral interface (SPI) devices. With plug‑and‑play USB connectivity, the USB‑8452 is a bus-powered, 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, toggling LEDs, or strobing convert and data ready lines common to analog converter chips. You can physically place the USB‑8452 more closely than PCI interfaces to I2C/SPI devices, which reduces I2C bus length and minimizes noise problems. Additionally, the interface provides +5 V and GND to power circuits with no external power supply.