The XR16V27511 (V2751) is a high performance dual universal asynchronous receiver and transmitter (UART) with 64 byte TX and RX FIFOs. The device operates from 2.25 to 3.6 volts with 5 Volt tolerant inputs and is pin-to-pin and software compatible to Exar's XR16L2751. The device includes 2 additional capabilities over the XR16V2750: Intel and Motorola data bus selection and a "PowerSave" mode to further reduce sleep current to a minimum during sleep mode. It supports the Exar's enhanced features of programmable FIFO trigger level and FIFO level counters, automatic hardware (RTS/CTS) and software flow control, automatic RS-485 half duplex direction control output and a complete modem interface. An internal loopback capability allows system diagnostics. Independent programmable fractional baud rate generators are provided in each channel to select data rates up to 8 Mbps at 3.3 Volt and 8X sampling clock. The V2751 is available in a 48-pin TQFP package.