XR21B1411IL-0A-EB

XR21B1411 ENHANCED 1-CH FULL-SPEED USB UART MAY 2018 REV. 1.2.2 GENERAL DESCRIPTION FEATURES  ±15kV HBM ESD on USBD+/USBD USB 2.0 Compliant, Full-Speed (12 Mbps) 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 12 Mbps USB data transfer rate. The USB interface also supports USB suspend, resume and remote wakeup operations. ■ Supports USB suspend, resume and remote wakeup operations  Unique preprogrammed USB serial number  Enhanced UART Features The XR21B1411 operates from an internal clock that is programmable to 6, 12, 24 or 48 MHz. Therefore, no external crystal / oscillator is required as in previous generation UARTs. With the fractional baud rate generator, any baud rate up to 12 Mbps can be accurately generated using the internal clock. The large 128-byte Tx FIFO and 384-byte Rx FIFO of the XR21B1411 help to optimize the overall data throughput for various applications. The automatic transceiver direction control feature simplifies both the hardware and software for half-duplex RS-485 applications. If required, the multidrop (9-bit) mode with automatic half-duplex transceiver control feature further simplifies typical multidrop RS-485 applications. The Vendor ID, Product ID, bus-powered mode, selfpowered mode, remote wakeup support or maximum power consumption values, as well as default baud rate settings can be programmed using the on-board OTP through the USBD+ / USBD- pins. ■ Data rates up to 12 Mbps ■ Fractional Baud Rate Generator ■ 128 byte TX FIFO ■ 384 byte 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 RS-485 Half-Duplex Control ■ Half-Duplex mode ■ Selectable GPIO or Modem I/O  Internal 48 MHz clock with clock divisors programmable down to 6 MHz  Single 5V power supply  5V tolerant inputs  16-pin QFN package  Virtual COM Port WHQL/HCK Windows certified The XR21B1411 operates from a single 5V power supply and is available in a 16-pin QFN package. WHQL certified software drivers for Windows XP, Vista, 7, 8, 8.1, 10 and CE, as well as Linux and Mac are supported for the XR21B1411. drivers APPLICATIONS ■ Windows XP, Vista, 7, 8, 8.1 and 10  Portable Appliances  External Converters (dongles)  Battery-Operated Devices  Cellular Data Devices  Factory Automation and Process Controls  Industrial applications ■ Windows CE 5.0, 6.0, 7.0  Linux, Mac drivers 1 XR21B1411 ENHANCED 1-CH FULL-SPEED USB UART REV. 1.2.2 FIGURE 1. XR21B1411 BLOCK DIAGRAM Internal Programmable Oscillator (6MHz – 48MHz) USBD+ USBD- USB Slave Interface USB Descriptors 1.6V-3.6V VIO_REF Fractional BRG Internal Status and Control Registers OTP 5V VCC GND 128-byte TX FIFO TX 384-byte RX FIFO RX GPIO5/RTS#/RS485 GPIO4/CTS# GPIO3/DTR# GPIO2/DSR# GPIO1/CD# GPIO0/RI# GPIOs/ Modem IO UART VCC USBD+ USBDGND FIGURE 2. PIN OUT DIAGRAM 16 15 14 13 LOWPOWER 1 12 VIO_REF NC 2 16-Pin QFN GPIO5/RTS#/RS485 3 10 RX 9 TX GPIO2/DSR# GPIO1/CD# GPIO0/RI#/RWK# 5 6 7 8 GPIO3/DTR# GPIO4/CTS# 4 11 VBUS_SENSE ORDERING INFORMATION(1) PART NUMBER OPERATING TEMPERATURE RANGE XR21B1411IL16-F -40°C to +85°C XR21B1411IL16TR-F -40°C to +85°C XR21B1411IL16MTR-F -40°C to +85°C XR21B1411IL-0A-EB LEAD-FREE Yes(2) PACKAGE 16-pin QFN Tray 16-pin QFN Tape and Reel 16-pin QFN Mini Tape and Reel XR21B1411 Evaluation Board NOTE: 1. Refer to www.exar.com/XR21B1411 for most up-to-date Ordering Information. 2. Visit www.exar.com for additional information on Environmental Rating. 2 PACKAGING METHOD XR21B1411 ENHANCED 1-CH FULL-SPEED USB UART REV. 1.2.2 PIN DESCRIPTIONS Pin Description 16-QFN PIN # TYPE DESCRIPTION RX 10 I UART Receive Data. This pin has a programmable pull-up or pull-down resistor which may be enabled by OTP programming. Pull-up resistor will be disabled without valid voltage on VIO_REF pin. TX 9 O UART Transmit Data. GPIO0/RI#/RWK# 8 I/O General purpose I/O or UART Ring-Indicator input (active low) or Remote Wakeup input. This pin has a programmable pull-up or pulldown resistor which may be enabled by OTP programming. This pin may also be used by any device to signal the USB host to exit the  Suspend state. See ”Section 1.3.10, USB Suspend” on page 9. GPIO1/CD# 7 I/O General purpose I/O or UART Carrier-Detect input (active low). This pin has a programmable pull-up or pull-down resistor which may be enabled by OTP programming. GPIO2/DSR# 6 I/O General purpose I/O or UART Data-Set-Ready input (active low). See NAME UART Signals ”Section 1.3.5.2, Automatic DTR/DSR Hardware Flow Control” on page 8. This pin has a programmable pull-up or pull-down resistor which may be enabled by OTP programming. GPIO3/DTR# 5 I/O General purpose I/O or UART Data-Terminal-Ready output (active low). See ”Section 1.3.5.2, Automatic DTR/DSR Hardware Flow Control” on page 8. This pin has a programmable pull-up or pull-down resistor which may be enabled by OTP programming. This bit will be automatically configured as an output when using the standard CDCACM driver. GPIO4/CTS# 4 I/O General purpose I/O or UART Clear-to-Send input (active low). See ”Section 1.3.5.1, Automatic RTS/CTS Hardware Flow Control” on page 8. This pin has a programmable pull-up or pull-down resistor which may be enabled by OTP programming. 3 I/O General purpose I/O or UART Request-to-Send output (active low) or auto RS-485 half-duplex control. See “Section 1.3.5.1, Automatic RTS/CTS Hardware Flow Control” on page 8 or “Section 1.3.6, Auto RS-485 Half-Duplex Control” on page 8. This pin has a programmable pull-up or pull-down resistor which may be enabled by OTP programming. This bit will be automatically configured for hardware flow control as RTS# output when using the standard CDC-ACM driver. USBD+ 15 I/O USB port differential data positive input. This pin has internal pull-up resistor compliant to USB 2.0 specification. The ESD protection on this pin is ±15 kV HBM. USBD- 14 I/O USB port differential data negative input. The ESD protection on this pin is ±15 kV HBM. GPIO5/RTS#/RS485 USB Interface Signals 3 XR21B1411 ENHANCED 1-CH FULL-SPEED USB UART REV. 1.2.2 Pin Description NAME 16-QFN PIN # TYPE DESCRIPTION 1 O The LOWPOWER pin will be asserted whenever it is not safe to draw the amount of current requested from VBUS in the Device Maximum Power field of the Configuration Descriptor. The LOWPOWER pin will behave differently for a low power device and a high power device. Miscellaneous Signals LOWPOWER ■ Low-power device (