XR16V794 HIGH PERFORMANCE 2.25V TO 3.6V QUAD UART WITH FRACTIONAL JULY 2008 REV. 1.0.1 FEATURES GENERAL DESCRIPTION 2.25V to 3.6V with 5V Tolerant Serial Inputs 1 The XR16V794 (794), is a 2.25V to 3.6V octal Single Interrupt output for all 4 UARTs Universal Asynchronous Receiver and Transmitter (UART) with 5V tolerant serial (modem) inputs. The A Global Interrupt Source Register for all 4 UARTs highly integrated device is designed for high 5G Flat UART Registers for easier programming bandwidth requirement in communication systems. Simultaneous Initialization of all UART channels The global interrupt source register provides a complete interrupt status indication for all 4 channels A General Purpose Command-driven 16-bit to speed up interrupt parsing. Each UART has its own Timer/counter 16C550 compatible set of configuration registers, TX Sleep Mode with Wake-up Indication and RX FIFOs of 64 bytes, fully programmable Highly Integrated Device for Space Saving transmit and receive FIFO trigger levels, TX and RX FIFO level counters, automatic RTS/CTS or DTR/ Each UART is independently controlled with: DSR hardware flow control with programmable 16C550 Compatible 5G Register Set hysteresis, autoamtic software (Xon/Xoff) flow 64-byte Transmit and Receive FIFOs control, RS-485 half-duplex direction control with Fractional Baud Rate Generator programmable turn-around delay, Intel or Motorola Transmit and Receive FIFO Level Counters bus interface and sleep mode with a wake-up indicator. Programmable TX and RX FIFO Trigger Level NOTE: Covered by US patents 5,649,122 and 5,949,787 Automatic RTS/CTS or DTR/DSR Flow Control Automatic Xon/Xoff Software Flow Control APPLICATIONS RS485 Half-Duplex Control Output with Remote Access Servers Selectable Turn-around Delay Ethernet Network to Serial Ports Infrared (IrDA 1.0) Data Encoder/Decoder Programmable Data Rate with Prescaler Network Management Up to 8 Mbps Serial Data Rate Factory Automation and Process Control Pin compatible to XR16L784. Same 64-pin LQFP Point-of-Sale Systems Package (10x10x1.4 mm) Multi-port RS-232/RS-422/RS-485 Cards FIGURE 1. BLOCK DIAGRAM *All Inputs are 5V Tolerant 2.25V to 3.6V VCC (Except XTAL1) GND UART Channel 0 64 Byte TX FIFO TX0, RX0, DTR0 , UART A7:A0 Regs DSR0 , RTS0 , TX & IR CTS0 , CD0 , RI0 RX ENDEC D7:D0 BRG Device 64 Byte RX FIFO IOR Configuration Register Intel or IOW s Motorola UART Channel 1 CS Data Bus INT Interface UART Channel 2 16/68 TX3, RX3, DTR3 , UART Channel 3 DSR3 , RTS3 , 16-bit RST CTS3 , CD3 , RI3 Timer/Counter ENIR Crystal Osc/ XTAL1 Buffer XTAL2 TMRCK Exar Corporation 48720 Kato Road, Fremont CA, 94538 (510) 668-7000 FAX (510) 668-7017 www.exar.com 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 XR16V794 HIGH PERFORMANCE 2.25V TO 3.6V QUAD UART WITH FRACTIONAL BAUD RATE REV. 1.0.1 FIGURE 2. PIN OUT OF THE DEVICE 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 XTAL2 ENIR XTAL1 TMRCK GND VCC VCC GND TX0 TX3 DTR0 DTR3 RTS0 RTS3 XR16V794 RI0 RI3 CD0 64-TQFP CD3 DSR0 DSR3 CTS0 CTS3 RX0 RX3 INT RST CS 16/68 A0 D7 A1 D6 11243 567 89011 1213 14 15 16 ORDERING INFORMATION PART NUMBER PACKAGE OPERATING TEMPERATURE RANGE DEVICE STATUS XR16V794IV 64-Lead LQFP -40C to +85C Active 2 TX1 A2 DTR1 A3 RTS1 A4 RI1 A5 CD1 A6 DSR1 A7 CTS1 IOR RX1 IOW TX2 VCC DTR2 GND RTS2 D0 RI2 D1 CD2 D2 DSR2 D3 CTS2 D4 RX2 D5 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 17