TP8485E ±12K ESD Protection, Full Fail-Safe RS-485 Transceiver

　　The TP8485E are 3V~5.5V powered transceivers that meet the RS-485 and RS-422 standards for balanced communication. Driver outputs and receiver inputs are protected against ±12kV ESD strikes without latch-up. Transmitters in this family deliver exceptional differential output voltages (2.5V min/5Vcc), into the RS-485 required 54Ω load, for better noise immunity, or to allow up to eight 120Ω terminations in “star” topologies. These devices have very low bus currents so they present a true “1/8 unit load” to the RS-485 bus. This allows up to 256 transceivers on the network without using repeaters. Receiver (Rx) inputs feature a “Full Fail-Safe” design, which ensures a logic high Rx output if Rx inputs are floating, shorted, or on a terminated but undriven bus. Rx outputs feature high drive levels - typically 25mA @ VOL = 1V (to ease the design of optocoupled isolated interfaces). The TP8485E is available in an SOIC-8 and MSOP-8 package, and is characterized from –40°C to 125°C.

　　Features

　　 Exceeds Requirements of EIA-485 Standard

　　 Hot Plug Circuitry - Tx and Rx Outputs Remain

　　Three-State During Power-up/Power-down

　　 Data Rate: Up to 250 kbps

　　 Full Fail-safe (Open, Short, Terminated)

　　Receivers

　　 Up to 256 Nodes on a Bus (1/8 unit load)

　　 Wide Supply Voltage 3V to 5.5V

　　 SOIC-8 Package for Backward Compatibility

　　 Bus-Pin Protection:

　　– ±12 kV HBM protection