MAX491CSD-TUDI

MAX491 is a low-power transceiver for RS-422 communications. Each device contains one driver and one receiver. The driver features an unconstrained slew rate, enabling data transmission up to 2.5Mbps. These transceivers consume supply current between 10μA and 500μA when the driver is disabled and the device is idle or fully loaded. All devices operate from a single 5V supply. The driver incorporates short-circuit current limiting and is protected by a thermal shutdown circuit that places the driver outputs in a high-impedance state to prevent excessive power dissipation. The receiver inputs feature a failsafe design that guarantees a logic-high output when the inputs are open-circuited. The MAX491 receiver input impedance is one-eighth unit load, allowing up to 256 transceivers to be connected to the bus. The MAX491 supports full-duplex communications.

Applications

• Low-power RS-485/RS-422 transceiver
• Transceiver for EMI-sensitive applications
• Industrial control LAN

Key features

• 4.5V to 5.5V supply voltage, supports RS485/RS422 full-duplex communication
• Fail-safe feature
• 1/8 unit load, allowing up to 256 devices on the bus
• Driver with short-circuit output protection
• Receiver with open-circuit fail-safe protection
• High noise immunity
• Integrated transient voltage suppression
• Data rate up to 2.5Mbps in electrically noisy environments
• A, B port protection: HBM ±15KV