The TSB43AB23 is a FireWire (IEEE 1394) physical layer interface device developed by Texas Instruments (TI). It was commonly integrated into motherboards, expansion cards, or devices requiring FireWire connectivity. This chip served as a bridge between the computer's internal buses and FireWire devices, enabling high-speed data transfer.

The TSB43AB23 supported the FireWire 400 standard (also known as IEEE 1394a), offering data transfer rates of up to 400 Mbps. It provided multiple ports for FireWire connections, facilitating the connection of peripherals such as external hard drives, digital cameras, and audio interfaces.

However, with the emergence of faster interfaces like USB 3.0 and Thunderbolt, FireWire usage has declined in favor of these newer and more widely adopted technologies. As a result, many modern systems may not feature FireWire ports or support due to its diminished popularity in recent years.