±15kV ESD-Protected, Isolated, 3.3V RS-485/RS-422 Data Interfaces

The MAX3480EA/MAX3480EB are electrically isolated RS-485/RS-422 data-communications interfaces. The RS-485/RS-422 I/O pins are protected against ±15kV electrostatic discharge (ESD) shocks, without latchup. Transceivers, optocouplers, and a transformer are all included in one low-cost, 28-pin PDIP package. A single +3.3V supply on the logic side powers both sides of the interface.

The MAX3480EB features reduced-slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission at data rates up to 160kbps. The MAX3480EA's driver slew rate is not limited, allowing transmission rates up to 2.5Mbps.

Drivers are short-circuit current limited and are protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-impedance state. The receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit.

The MAX3480EA/MAX3480EB are guaranteed to withstand 1260VRMS (1min) or 1520VRMS (1s). Their isolated inputs and outputs meet RS-485/RS-422 specifications.

Applications

* Automated Test Equipment (ATE) * HVAC/Building Control Networks * Industrial Control Local Area Networks * Isolated RS-485/RS-422 Data Interface * Telecom * Transceivers for EMI-Sensitive Applications

* Isolated Data Interface Guaranteed to 1260VRMS (1min)

* ±15kV ESD Protection for I/O Pins

* Slew-Rate-Limited Data Transmission (160kbps for MAX3480EB)

* High-Speed, Isolated, 2.5Mbps RS-485 Interface (MAX3480EA)

* Single +3.3V Supply

* Current Limiting and Thermal Shutdown for Driver Overload Protection

* Standard 28-Pin PDIP Package

* Allows Up to 128 Transceivers on the Bus