XR21B1422IL40-F

XR21B1422 Enhanced 2-Ch Full-Speed USB UART General Description FEATURES The XR21B1422 is an enhanced Universal Asynchronous Receiver and Transmitter (UART) bridge to USB interface. The USB interface is fully compliant to the USB 2.0 (Full-Speed) specification with 12 Mbps USB data transfer rate. The USB interface also supports USB suspend, resume and remote wakeup operations. The USB Vendor ID, Product ID, power mode, remote wakeup support, maximum power, and numerous other settings may be programmed in the on-chip OTP memory via the USB interface. • ±15kV ESD on USBD+/USBD• USB 2.0 Compliant, Full-Speed (12Mbps) • Unique pre-programmed USB serial number • Internally generated 48MHz core clock • Enhanced UART features • Baud rates from 300 bps to 12 Mbps • Fractional Baud Rate Generator • 512-byte TX and 512-byte RX FIFOs • Auto Hardware / Software Flow Control • Multidrop and Half-Duplex Modes • Auto RS-485 Half-Duplex Control • Selectable GPIO or Modem I/O • Up to 10 GPIOs per channel • 5V tolerant GPIO inputs • Suspend state GPIO configuration • Configurable clock output • 40-pin QFN package The XR21B1422 includes an internal oscillator and does not require an external crystal/oscillator. Any UART baud rate from 300 bps to 12 Mbps may be generated with this internal clock and the fractional baud rate generator. The UART pins for each port may also be configured as GPIO; direction, state, output driver type and input pull-up or pull-down resistors are programmed either through on chip OTP, or on the fly via memory mapped registers. Large 512-byte TX and RX FIFOs prevent buffer overflow errors and optimize data throughput. Automatic half-duplex direction control and optional multi drop (9-bit) mode simplify both hardware and software in half-duplex RS-485 applications. Wide mode allows for each individual received character to be monitored for errors. • Industrial -40°C to +85°C Temperature Range APPLICATIONS • Building Automation • Security Systems • Factory and Process Control • ATM Terminals The XR21B1422 uses the native OS CDC-ACM driver or a MaxLinear supplied custom driver. MaxLinear provides WHQL-certified software drivers for Windows XP, Vista, 7, 8, 8.1,10, and 11 as well as custom software drivers for Linux. Full source code is available. • USB to Serial Controllers Ordering Information - page 62 Block Diagram VIO Internal Oscillator (48MHz) USB Fractional BRG 512-byte TX FIFO TX 512-byte RX FIFO RX Throughput Comparison 1840k 1610k 1380k USB Slave Interface USB Descriptors Internal Status and Control Registers Competitor MaxLinear 1150k GPIOs/ Modem IO OTP 920k 690k 460k 230k UART Ch A LDO 3V3 • www.maxlinear.com • 272DSR00 UART Ch B (same as Ch A) 0k 230k 460k 920k Data Rate (bps) 1840k XR21B1422 Absolute Maximum Ratings Operating Conditions Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Maximum Rating may affect device reliability and lifetime. Operating Temperature Range.....................-40°C to +85°C Supply Voltage (VCC_REG)......................................+5.75V Supply Voltage (VCC, VIO)............................................+4V Input Voltage (VBUS_SENSE).......................-0.3 to +5.75V Input Voltage (All other pins)............................-0.3 to +5.6V Junction Temperature.................................................125°C Electrical Characteristics Unless otherwise noted: TA = -40°C to +85°C, VCC_REG = +4.4V to +5.25V or +3.0V to +3.6V, VIO = +1.8V to +3.6V. Symbol Parameter Conditions Min Typ Max Units 15 23 mA 0.85 1.25 mA 3.3 3.6 V Power ICC Power Supply Current ISUSP Suspend Mode Current VOUT Regulated Output Voltage (VCC pin) VCC_REG = +4.4V to +5.25V (Does not include current that VOUT sources to external devices or to VIO) VCC_REG = +4.4V to +5.25V. Maximum output current = 200 mA including the supply current of the XR21B1422. 3 UART, USB_STAT and GPIO Pins VIL Input Low Voltage -0.3 0.25* VIO V VIH Input High Voltage 0.70* VIO 5.5 V VOL Output Low Voltage IOL = 1mA, VIO = +1.6V 0.3 V IOL = 4mA, VIO = +3.6V 0.5 V VOH Output High Voltage IOH = -400uA, VIO = +1.6V 1.3 VIO V IOH = -1.5mA, VIO = +3.6V 2.8 VIO V IIL Input Low Leakage Current VIO = +3V to +3.6V, VCC_REG = +4.4V to +5.25V, VINPUT = 0V ±10 µA IIH Input High Leakage Current VIO = +3V to +3.6V, VCC_REG = +4.4V to +5.25V, VINPUT = +3.3V ±10 µA VIO = +3V to +3.6V, VCC_REG = +4.4V to +5.25V, VINPUT = +5.5V ±120 µA 5 pF CIN 272DSR00 Input Pin Capacitance 2 Rev. 1E XR21B1422 Symbol Parameter Conditions Min Typ Max Units USB I/O Pins VIL Input Low Voltage -0.3 0.8 V VIH Input High Voltage 2.0 5.5 V VOL Output Low Voltage External 15kΩ to GND on USBD+ and USBD- pins 0 0.3 V VOH Output High Voltage External 15kΩ to GND on USBD+ and USBD- pins 2.8 3.6 V VDrvZ Driver Output Impedance 28 44 Ω 272DSR00 3 Rev. 1E XR21B1422 RXA GPIOA5/RTSA#/RS485A GPIOA4/CTSA# GPIOA3/DTRA# GPIOA2/DSRA# GPIOA1/CDA# GPIOA0/RIA#/RWKA# 34 33 32 31 TXA 35 GPIOA6/CLKA 36 38 37 39 1 MaxLinear XR21B1422 30 GPIOB0/RIB#/RWKB# 29 GPIOB1/CDB# 28 GPIOB2/DSRB# GPIOA9/RXTA 2 NC 3 NC 4 27 GPIOB3/DTRB# GND 5 26 GPIOB4/CTSB# USBD+ 6 25 GND USBD- 7 24 VIO VIO 8 23 GPIOB5/RTSB#/RS485B VCC 9 22 RXB 21 TXB E_PAD USB_STAT1 GPIOB9/RXTB NC USB_STAT2 GPIOB6/CLKB NC GPIOB7/RS485B 16 GPIOB8/TXTB 15 20 14 19 13 18 12 4 17 11 RESET# 10 VBUS_SENSE VCC_REG 272DSR00 40 GPIOA8/TXTA GPIOA7/RS485A Pin Configuration Rev. 1E XR21B1422 Pin Assignments Pin No. Pin Name Type Description 1 GPIOA8/TXTA I/O General purpose I/O, or UART transmit data indicator. Defaults to GPIO input with internal pullup resistor. See “TXT and RXT Pins” on page 18. When configured as transmit indicator, this pin will toggle at ~10Hz intervals while the UART is transmitting data. 2 GPIOA9/RXTA I/O General purpose I/O, or UART receive data indicator. Defaults to GPIO input with internal pullup resistor. See “TXT and RXT Pins” on page 18. When configured as receive indicator, this pin will toggle at ~10Hz intervals while the UART is receiving data. 3 NC - No Connect. MaxLinear recommends to connect this pin to the ground. 4 NC - No Connect. MaxLinear recommends to connect this pin to the ground. 5 GND 6 USBD+ I/O USB port differential data positive. This pin has internal pull-up resistor compliant to the USB 2.0 specification. The ESD protection on this pin is ±15kV HBM. 7 USBD- I/O USB port differential data negative. The ESD protection on this pin is ±15kV HBM. 8 VIO PWR I/O voltage input to the UART/GPIO pins. Must be between 1.8 and 3.6V. May be connected to VCC (pin 12) if VCC_REG input voltage is 5V. See “USB Power Modes” on page 11. 9 VCC PWR 3.3V power to the device, or 3.3V power output from the device when 5V power is supplied to VCC_REG pin. 3.3V output power can source up to 200 mA maximum (including the device) and should be decoupled by minimum of 4.7µF ceramic capacitor. See “USB Power Modes” on page 11. 10 VCC_REG PWR 5V or 3.3V power to the device. In bus-powered mode, connect VBUS (5V) power from the USB host to this pin and to the VBUS_SENSE pin - see Figure 1.To conform to USB specifications, an inrush current limiting circuit is recommended. In self-powered mode, connect onboard 5V or 3.3V source to this pin and VBUS from the USB host to the VBUS_SENSE pin. See Figure 2 and Figure 3. USB specification requires a minimum of 1uF and a maximum of 10uF of decoupling on VBUS power. 11 VBUS_SENSE I Must be connected to VBUS power from the USB host PC. This pin is used to disable the internal pull-up resistor on the USBD+ signal when VBUS is not present. In bus-powered mode, connect VBUS (5V) power from the USB host to this pin and to the VCC_REG pin - see Figure 1. In self-powered mode, connect VBUS from the USB host to this pin. This pin must be decoupled by a 4.7 uF tantalum capacitor. 12 RESET# I/O OD Active low open drain output. Asserted at power on or any time device is reset by either register or USB bus reset. As an input, must be asserted for at least 15µs to force a device reset. Reset pulse width input of shorter than 15µs will have unknown effects. A weak internal pull-up resistor provides noise immunity if left unconnected. 13 NC 14 USB_STAT2 272DSR00 PWR O / OD Power supply common, ground. No Connect. MaxLinear recommends to connect this pin to the ground. This pin has the same functionality as the USB_STAT1 pin. However, the default output for this pin is active low polarity, asserted whenever the XR21B1422 is placed into a suspended state. This default may be changed via the PIN_CFG_USB_STAT2 register. 5 Rev. 1E XR21B1422 Pin No. Pin Name Type Description 15 USB_STAT1 O The USB_STAT1 output pin may be used to indicate any of three USB status conditions: 1. USB_STAT1 is asserted when the USB host asserts USB reset. 2. USB_STAT1 is asserted when the USB host PC places the XR21B1422 device into the suspended state. 3. USB_STAT1 is asserted when it is not safe to draw the amount of current requested in the Device Maximum Power field of the Configuration Descriptor. a. For a low power device (