The National Instruments 781420-16, also known as the NI 2816A, is a high-density matrix switch card designed for integration within the NI SwitchBlock system. Engineered to facilitate the creation of extensive switching matrices, the 781420-16 allows for easy scalability, enabling users to expand their test configurations by adding multiple cards within a single chassis. This matrix switch card supports a variety of applications involving moderate voltage and current loads, with a maximum switching voltage of 100 VDC or 70 VAC and a per-channel switching current of up to 0.25 A. It features a maximum carry current of 0.3 A, ensuring reliable performance under continuous load conditions, and a maximum switching power rating of 3 W per channel and at each crosspoint, accommodating moderate power demands.

Designed for optimum performance, the 781420-16 exhibits low initial DC path resistance of less than 1 Ω, which minimizes signal loss during switching. Throughout its service life, the resistance may increase yet remains within a manageable threshold of greater than 2 Ω at end-of-life. In instances of an open channel, the resistance can exceed 1 × 10^9 Ω. The card utilizes reed relays that are rated for a mechanical relay life of up to 2.5 × 10^8 cycles under no load, supporting high-speed switching applications with the capability to drive up to 61 relays simultaneously. The typical relay operate and release times are under 1 ms for up to 8 relays and less than 2 ms for configurations involving up to 50 relays, making it suitable for automated testing environments requiring prompt signal transitions.

Power consumption efficiency is notable as each relay on the card consumes 63 mW, with a collective power consumption limit of 3.9 W per card. The physical attributes include a compact and lightweight design, measuring 11.2 cm x 1.2 cm x 17.1 cm and weighing 320 g. It functions effectively across a broad range of environmental conditions, with an operational temperature range from 0 °C to 55 °C and a storage temperature range from -20 °C to 70 °C, supporting versatility in various applications.