XR21V1414 4-CH FULL-SPEED USB UART DECEMBER 2013 REV. 1.3.0 FEATURES GENERAL DESCRIPTION USB 2.0 Compliant, Full-speed (12 Mbps) The XR21V1414 (V1414) is an enhanced 4-channel USB Universal Asynchronous Receiver and Supports USB suspend, resume and remote Transmitter (UART). The USB interface is fully wakeup operations compliant to Full Speed USB 2.0 specification that 5 kV HBM ESD protection on USB data pins supports 12 Mbps USB data transfer rate. The USB interface also supports USB suspend, resume and 2 kV HBM ESD protection on all other pins remote wakeup operations. Enhanced Features of each UART The V1414 operates from an internal 48MHz clock UART data rates up to 12 Mbps therefore no external crystal/oscillator is required like Fractional Baud Rate Generator previous generation UARTs. With the fractional baud rate generator, any baud rate can accurately be 128 byte TX FIFO generated using the internal 48MHz clock. 384 byte RX FIFO The large 128-byte TX FIFO and 384-byte RX FIFO 7, 8 or 9 data bits of the V1414 helps to optimize the overall data 1 or 2 stop bits throughput for various applications. If required, the Odd, even, mark, space, or no parity multidrop mode and automatic RS-485 half-duplex Automatic Hardware (RTS/CTS or DTR/DSR) direction control feature further simplifies typical Flow Control multidrop RS-485 applications. Automatic Software (Xon/Xoff) Flow Control The V1414 operates from a single 2.97 to 3.63 volt Multidrop mode power supply and has 5V tolerant inputs. The V1414 is available in a 48-pin TQFP package. Auto RS-485 Half-Duplex Control Half-Duplex mode WHQL certified software drivers for Windows 2000, XP, Vista, 7, 8, and CE, as well as Linux and Mac are Selectable GPIO or Modem I/O supported for the XR21V1414. Internal 48 MHz clock APPLICATIONS Single 3.3V power supply Portable Appliances 5V tolerant inputs External Converters (dongles) 48-pin TQFP package Battery-Operated Devices Virtual COM Port WHQL certified drivers Cellular Data Devices Windows 2000, XP Vista, Win7 and Win8 Windows CE 4.2, 5.0, 6.0, 7.0 Factory Automation and Process Controls Linux Industrial applications Mac Exar Corporation 48720 Kato Road, Fremont CA, 94538 (510) 668-7000 FAX (510) 668-7017 www.exar.com XR21V1414 4-CH FULL-SPEED USB UART REV. 1.3.0 FIGURE 1. XR21V1414 BLOCK DIAGRAM 128-byte TXA TX FIFO Fractional 3.3V VCC 3.3V to 1.2V BRG GND 384-byte RXA Regulator RX FIFO GPIOA5/RTSA /RS485A GPIOA4/CTSA Internal GPIOA3/DTRA Status and GPIOs/ GPIOA2/DSRA Control Modem IO GPIOA1/CDA Registers GPIOA0/RIA USB Slave DATA+ UART Channel A Interface DATA- TXB UART Channel B RXB (Same as Ch A) GPIOB 5:0 /ModemIO 2 SDA I C SCL Interface TXC UART Channel C RXC (Same as Ch A) GPIOC 5:0 /ModemIO Internal 48MHz TXD UART Channel D RXD Oscillator (Same as Ch A) GPIOD 5:0 /ModemIO 2