The NI-9221 is a C Series Voltage Input Module manufactured by National Instruments, designed for high-performance single-ended analog input applications. This module supports an analog input voltage range of -60 V to 60 V, with a maximum sample rate of 800 kS/s and a resolution of 12 bits across eight single-ended analog input channels. It is primarily suitable for applications within various industries, including automotive testing and battery management systems. The NI-9221 does not feature differential analog input channels or simultaneous sampling capabilities.

Available in multiple configurations, the NI-9221 has variations that differ only in connector types, including a 10-position screw terminal, a 25-position D-Sub connector, and a spring terminal. The D-Sub connector is particularly cost-effective, offering compatibility with a wide range of accessories available from National Instruments and other vendors, and allowing for customized cable solutions tailored to specific applications. For enhanced connectivity with the CompactRIO hardware platform, NI recommends using the NI 9932 strain-relief connector.

The module operates with NI-DAQ driver software, which is compatible with various application development environments, including LabVIEW, LabWindows/CVI, C/C++, C#, and Visual Basic .NET. It has a maximum power consumption of 1 W while active and only 1 mW in sleep mode. The module's dimensions and weight vary by connector type, weighing 5.0 oz for the D-Sub variant, 5.4 oz for the spring terminal, and 5.8 oz for the screw terminal model. The recommended operating temperature range is from -40 °C to 70 °C, with a storage temperature range of -40 °C to 85 °C. For detailed specifications and further information, please refer to the product's technical documentation available on the National Instruments website.