The DS2480B is a serial port to 1-Wire® interface chip that supports standard and overdrive speeds. It connects directly to UARTs and 5V RS-232 systems. Interfacing to RS-232C (±12V levels) requires a passive clamping circuit and one 5V to ±12V level translator. Internal timers relieve the host of the burden of generating the time-critical 1-Wire communication waveforms. In contrast to the DS9097(E) where a full character must be sent by the host for each 1-Wire time slot, the DS2480B can translate each character into eight 1-Wire time slots, thereby increasing the data throughput significantly. In addition, the DS2480B can be set to communicate at four different data rates, including 115.2kbps, 57.6kbps, and 19.2kbps, with 9.6kbps being the power-on default. Command codes received from the host"s crystal controlled UART serve as a reference to continuously calibrate the on-chip timing generator. The DS2480B uses a unique protocol that merges data and control information without requiring control pins. This approach maintains compatibility to off-the-shelf serial to wireless converters, allowing easy realization of 1-Wire media jumpers. The various control functions of the DS2480B are optimized for 1-Wire networks and support the special needs of all current 1-Wire devices including EPROM-based add-only memories, EEPROM devices, and 1-Wire thermometers. See Application Note 192: Using the DS2480B Serial 1-Wire Driver for detailed software examples.
