SN75176-IDC

SN75176 is a transceiver IC for RS485 and RS422 communication systems, supporting data rates up to 2.5Mbps. The device operates in half-duplex mode and features Driver Enable (DE) and Receiver Enable (/RE) control pins. The receiver input impedance is 1/4 unit load, allowing up to 128 loads to be connected in parallel on the same bus. The device incorporates a slew-rate-limited driver to reduce EMI and signal reflections caused by improper cable termination. The receiver features input filtering and hysteresis for improved noise immunity, at the cost of a 25% increase in propagation delay. No fail-safe circuitry is integrated; when the differential input voltage is between -200mV and +200mV, the receiver output state is indeterminate. When the bus is idle, a pull-up resistor on port A is recommended to ensure a high receiver output. The driver output stage includes foldback current limiting and thermal shutdown protection against damage from short circuits or bus contention. The transceiver is suited for bidirectional data communication on multipoint buses and can also be used as a line repeater for long cables.

Applications

• Low-power RS485 and RS422 receiver
• Electric, water, and gas meters
• Level translation
• Access control and security systems
• EMI-resistant transceiver
• Industrial control LAN

Key features

• Three-state output
• Half-duplex communication
• ESD protection: contact discharge ±5KV, air discharge ±5KV (HBM)
• A/B port short-circuit protection
• SOP8 package