National Instruments 779421-01 Multifunction I/O Device

The part number 779421-01 from National Instruments is the identifying part number for the PCI-6133 Multifunction I/O Device. The this multifunctional device features 8 differential analog input channels which can convert the signal to digital format with the help of a 14-bit analog-to-digital converter. The 14-bit resolution allows this module to convert the analog signal into a more precise digital signal by breaking the signal into 16,384 voltage levels allowing for accurate data capture of the signal for further processing. The module has a maximum sampling rate of 2.5 Mega samples per second on a single channel allowing the module to capture data very quickly. The module also has an input impedance of 100 MΩ which helps prevent noise in the signal and all the channels have 10 pF of capacitors connected in parallel with them to ensure minimal loading on the signal source. The module has an overvoltage protection of ±36 Volts protecting the module from voltage spikes.

The 779421-01 Multifunction I/O Device has input voltage ranges with ±11 Volts maximum working voltage for all analog input channels. The typical input bias current is ±2 pA, and the maximum is ±25 pA, to minimize offset errors. The device includes a 16 MS First In First Out buffer to acquire data without data loss, and it supports multiple data transfer modes, including DMA, interrupts, and programmed I/O. In addition, it has integral nonlinearity of ±0.6 Least significant bit typical and ±1 Least significant bit maximum, and a differential nonlinearity of ±0.25 Least significant bit typical and ±0.75 Least significant bit maximum.

Thus module includes a phase mismatch of ±2° at 1 MHz, a system noise of 0.78 LSBrms at ±10 Volts range, and a total harmonic distortion of -101.1 dB at 10 kHz for the ±10 Volts range. The signal-to-noise and distortion ratio and spurious-free dynamic range are important parameters for high-fidelity signal acquisition.

The 779421-01 Multifunction I/O Device features 8 digital I/O lines compatible with TTL/CMOS logic levels. These can be user-programmed for input or output via compatible drivers and software. The module also features two 24-bit counters or timers and a 4-bit frequency scaler, supporting up-and-down counting and precise timing operations. The device supports both analog and digital triggering.