The SN55LBC172 is a monolithic quadruple differential line driver with 3-state outputs. This device is designed to meet the requirements of the Electronics Industry Association (EIA) standard RS-485. The SN55LBC172 is optimized for balanced multipoint bus transmission at data rates up to and exceeding 10 million bits per second. The driver features wide positive and negative common-mode output voltage ranges, current limiting, and thermal-shutdown circuitry, making it suitable for party-line applications in noisy environments. The device is designed using the LinBiCMOS™ process, facilitating ultralow power consumption and inherent robustness. The SN55LBC172 provides positive- and negative-current limiting and thermal shutdown for protection from line fault conditions on the transmission bus line. This device offers optimum performance when used with the SN55LBC173M quadruple line receiver.