The XR18W750 is a wireless UART controller with an I2C interface to the XR18W753 RF transceiver to complete Exar’s wireless UART chipset solution. The XR18W750 supports both the parallel and serial interfaces to any host system thus providing flexibility for system designers to select their interface option. The XR18W750 includes an embedded 8051 microprocessor which provides the power to process the protocol framing for data transmission and to handle error processing. Internally, the XR18W750 has 32KB system memory for data processing. The XR18W750 also includes a 128-bit AES engine for data encoding and decoding.

The XR18W753 is a single-chip RF transceiver designed to operate in license-free North American 915MHz ISM, European 868MHz SRD, and 950MHz to 956MHz bands for low-power, short-range wireless applications. Direct Sequence Spread Spectrum (DSSS) technique is employed to provide robust data communication in signal congested RF environments. The device provides extensive hardware support for packet handling, data buffering, packet timing, RSSI, energy detection, link quality indication, clear channel assessment, FCS computation, and CRC detection. RF output power is programmable from -24 dBm to 0 dBm with a maximum data rate of 250Kbps.