Products

The SN65HVD178x and SN65HVD1791 are ±70V, fault-protected, half duplex and full duplex, respectively, 5-V RS-485 transceivers in speed grades of 128 kbps, 1 Mbps and 10 Mbps. The bus pins can be shorted indefinitely to line voltages of up to ±70 V with no damage.

These devices are designed to survive overvoltage faults such as direct shorts to power supplies, mis-wiring faults, connector failures, cable crushes, and tool mis-applications. They are also robust to ESD events, with high levels of protection to human-body model specifications.

These devices combine a differential driver and a differential receiver, which operate from a single power supply. In the 'HVD1785, 'HVD1786, and 'HVD1787, the driver differential outputs and the receiver differential inputs are connected internally to form a bus port suitable for half-duplex (two-wire bus) communication. In the 'HVD1791, the driver differential outputs and the receiver differential inputs are separate pins, to form a bus port suitable for full-duplex (four-wire bus) communication. These ports feature a wide common-mode voltage range, making the devices suitable for multipoint applications over long cable runs.  

• Bus-pin fault protection to > ±70 V
• Wide common-mode voltage range (-20 V...+25 V) more than doubles TIA/EIA 485 requirement
• Bus I/O protection
• ±16 kV JEDEC HBM protection
• Reduced unit load for up to 256 nodes
• Failsafe receiver for open-circuit, short-circuit and idle-bus conditions
• low power consumption
• Low standby supply current: 1 µA typ
• ICC 5 mA quiescent during operation
• Power-up, power-down glitch-free operation
• Operating temperature: -40°C...+105 °C

Designed for RS-485 and RS-422 networks such as:

• HVAC
• battery-powered systems
• power inverters
• industrial automation
• motor control
• telecommunications equipment