2.75kV Isolated 500kbps Half-Duplex RS-485/RS-422 Transceiver with ±30kV ESD Protection

The MAX14945 isolated RS-485/RS-422 transceiver provides 2750VRMS (60s) of galvanic isolation between the cable side (RS-485/RS-422 driver/receiver side) and the UART side of the device. Isolation improves communication by breaking ground loops and reduces noise when there are large differences in ground potential between ports. Signals are passed across the isolation barrier through integrated high-voltage capacitors. This device allows for robust communication at any speed up to 500kbps.

The device includes one half-duplex drive/receive channel. The receiver is 1/8-unit load, allowing up to 256 transceivers on a common bus.

Integrated true fail-safe circuitry ensures a logic-high on the receiver output when inputs are shorted or open. Undervoltage lockout disables the driver when the cable side or UART side power supplies are below functional levels.

The driver outputs/receiver inputs are protected from ±30kV electrostatic discharge (ESD) to GNDB on the cable side, as specified by the Human Body Model (HBM).

The MAX14945 is available in a wide body 16-pin SO package and operates over the -40°C to +85°C temperature range.

Applications

* HVAC * Industrial Automation Equipment * Power Meters * Programmable Logic Controllers

* High-Performance Transceiver Enables Flexible Designs

* Integrated LDO for Cable-Side Power

* Compliant with RS-485 EIA/TIA-485 Standard

* 500kbps Maximum Data Rate

* Allows Up to 256 Devices on the Bus

* Integrated Protection Ensures Robust Communication

* ±30kV ESD (HBM) on Driver Outputs/Receiver Inputs

* 2.75kVRMS Withstand-Isolation Voltage for 60s (VISO)

* 630VPEAK Maximum Repetitive Peak-Isolation Voltage (VIORM)

* 445VRMS Maximum Working-Isolation Voltage (VIOWM)

* > 30 Years Lifetime at Rated Working Voltage

* Withstands ±10kV Surge per IEC 61000-4-5

* Thermal Shutdown