MAX3140EEI+T

The MAX3140EEI+T from Analog Devices combines a universal asynchronous receiver-transmitter (UART) with a true fail-safe RS-485/RS-422 transceiver in a compact 28-pin QSOP package. This integration saves board space and microcontroller I/O pins by featuring an SPI/QSPI/MICROWIRE-compatible serial interface.

The device offers true fail-safe receiver circuitry, ensuring a logic-high output when receiver inputs are open or shorted, eliminating the need for complex termination. It supports software-selectable half- or full-duplex operation, programmable data rates up to 10Mbps, and slew rate control for reduced EMI. The UART includes an 8-word-deep receive FIFO and supports baud rates from 300 to 230k baud.

Designed for space- and power-constrained applications, the MAX3140EEI+T operates from a single +5V supply, consuming typically 645µA with the receiver active. A hardware-invoked shutdown mode reduces supply current to just 20µA. The receiver input impedance allows up to 256 transceivers on the bus.

Applications include industrial control, HVAC and building control, point-of-sale devices, embedded systems, and intelligent instrumentation where reliable serial communication is essential.