The XR21B1411 is an enhanced Universal Asynchronous Receiver and Transmitter (UART) with a USB interface. The USB interface is fully compliant to Full Speed USB 2.0 specification that supports 12Mbps USB data transfer rate. The USB interface also supports USB suspend, resume and remote wakeup operations.

±15kV HBM ESD on USBD+/USBD-
USB 2.0 Compliant, Full-Speed (12Mbps)
Supports USB suspend, resume and remote wakeup operations
Unique pre-programmed USB serial number
Enhanced UART Features
Fractional Baud Rate Generator
128byte TX FIFO
384byte RX FIFO
7, 8 or 9 data bits
1 or 2 stop bits
Odd, even, mark, space or no parity
Automatic Hardware (RTS/CTS or DTR/DSR) Flow Control
Automatic Software (Xon/Xoff) Flow Control
Multidrop mode
Auto Transceiver Control
Half-Duplex mode
Selectable GPIO or Modem I/O
Internal 48MHz clock with clock divisors programmable down to 6MHz
Single +5V power supply
5V tolerant inputs