The National Instruments USB-6221 is a versatile Multifunction I/O device from the M Series, designed to meet a wide range of automation and control applications. It features 16 single-ended analog input channels, which can be configured as 8 differential channels, enhancing flexibility for diverse connectivity needs. The device is equipped with 2 analog output channels and 24 digital I/O lines, both capable of acquiring samples at a maximum rate of 250 kS/s. The USB-6221 supports correlated digital I/O, analog I/O, digital triggering, and includes two 32-bit timers, making it ideal for manufacturing tests, laboratory automation, design validation, and research applications.

Various part numbers offer different voltage options catering to international standards, including part numbers for the USA (780117-01, 120 V), Switzerland (780117-02, 220 V), Australia (780117-03, 240 V), and the U.K. (780117-06, 240 V), among others. The board-only version is available as part number 195959-02. The device supports high-voltage measurements using compatible signal conditioning accessories and provides digital I/O lines capable of pulse-width modulation, enabling control of various equipment like lamps, pumps, and motors, with output signals of 24 mA. Connectivity options include a single 68-pin VHDCI connector for PCI/PXI, as well as USB screw terminals and USB BNC connectors.

Though marked as obsolete by National Instruments, the USB-6221 remains available through Apex Waves for purchase and repair services. The dimensions for the screw terminal version are 10.5 in. × 6.73 in. × 1.75 in., weighing 2 lb 10 oz, while the OEM version weighs 4.6 oz. The device includes a warranty of 2-3 years, and both user and maintenance manuals are available for download. For pricing information, please contact a sales representative.