XR20M1172 Datasheet | Exar

DESCRIPTION The XR20M11721 (M1172) is a high performance two channel universal asynchronous receiver and transmitter (UART) with 64 byte TX and RX FIFOs and a selectable I2C/SPI slave interface. The M1172 operates from 1.62 to 3.63 volts. The standard features include 16 selectable TX and RX FIFO trigger levels, automatic hardware (RTS/CTS) and software (Xon/Xoff) flow control, and a plete modem interface. Onboard registers provide the user with operational status and data error flags. An internal loopback capability allows system diagnostics. Additional enhanced features includes a programmable fractional baud rate generator and 8X and 4X sampling rate that allows for a maximum baud rate of 16 Mbps at 3.3V. The M1172 is available in the 32-pin QFN and 28-pin TSSOP packages. The 32pin QFN package has the EN485# and ENIR# pins to allow the UART to power-up in the Auto RS485 mode or the Infrared mode. NOTE: 1 Covered by U.S. Patent #5,649,122 FEATURES - 1.62 to 3.6 Volt Operation - Selectable I2C/SPI Interface - Full-featured UART - - - - - - - - - - Data rate of up to 16 Mbps at 3.3 V Data rate of up to 12.5 Mbps at 2.5 V Data rate of up to 8 Mbps at 1.8 V Fractional Baud Rate Generator Transmit and Receive FIFOs of 64 bytes 16 Selectable TX and RX FIFO Trigger Levels Automatic Hardware (RTS/CTS) Flow Control Automatic Software (Xon/Xoff) Flow Control Halt and Resume Transmission Control Automatic RS-485 Half-duplex Control Output via RTS# Direction - Wireless Infrared (Ir DA 1.0 and 1.1) Encoder/ Decoder Automatic sleep mode (< 30 u A at 3.3V) General Purpose I/Os Full modem interface - - - APPLICATIONS - Portable Appliances - Battery-Operated Devices - Cellular Data Devices - Factory Automation and Process Controls FIGURE 1. XR20M1172 BLOCK DIAGRAM - Crystal oscillator (up to 24MHz) or external clock (up to 64MHz) input - 32-QFN and 28-TSSOP packages VCC E N IR # E N 485# IR Q # RESET# SDA SCK A 0/ C S # A 1/S I SO I2 C / S P I# 1 . 6 2 V - 3 . 6 3V C...