xr XR16L2752 2.25V TO 5.5V DUART WITH 64-BYTE FIFO MAY 2005 REV. 1.2.1 FEATURES GENERAL DESCRIPTION 2.25 to 5.5 Volt Operation 1 The XR16L2752 (2752) is a low voltage dual 5 Volt Tolerant Inputs universal asynchronous receiver and transmitter (UART) with 5 Volt tolerant inputs. The device Pin-to-pin compatible to Exars ST16C2552 and operates from 2.25 to 5.5 Volt supply range and is XR16C2852 pin-to-pin compatible to Exars ST16C2552 and Larger FIFO version of PC16C552 XR16C2852. The 2752 register set is compatible to Two independent UART channels the ST16C2552 and the XR16C2852 enhanced features. It supports the Exars enhanced features of Reg set compatible to 16C2552 and 16C2852 64 bytes of TX and RX FIFOs, programmable FIFO Up to 6.25 Mbps at 5 Volt, 4 Mbps at 3.3 Volt trigger level and FIFO level counters, automatic and 3 Mbps at 2.5 Volt with 8X sampling rate hardware (RTS/CTS) and software flow control, Transmit and Receive FIFOs of 64 bytes automatic RS-485 half duplex direction control output Programmable TX and RX FIFO Trigger Levels and a complete modem interface. Onboard registers Transmit and Receive FIFO Level Counters provide the user with operational status and data Automatic Hardware (RTS/CTS) Flow Control error flags. An internal loopback capability allows system diagnostics. Independent programmable Selectable Auto RTS Flow Control Hysteresis baud rate generators are provided in each channel to Automatic Software (Xon/Xoff) Flow Control select data rates up to 6.25 Mbps at 5 Volt and 8X Automatic RS-485 Half-duplex Direction sampling. The 2752 is available in the 44-pin PLCC Control Output via RTS package. Wireless Infrared (IrDA 1.0) Encoder/Decoder NOTE: 1 Covered by U.S. Patent 5,649,122 and 5,949,787 Automatic sleep mode APPLICATIONS Full modem interface Alternate Function Register Portable Appliances Device Identification and Revision Telecommunication Network Routers Crystal oscillator or external clock input Ethernet Network Routers Industrial and commercial temperature ranges Cellular Data Devices 44-PLCC package Factory Automation and Process Controls FIGURE 1. XR16L2752 BLOCK DIAGRAM 2.25 V to 5.5 V VCC *5 Volt Tolerant Inputs A2:A0 GND (Except External Clock Input) D7:D0 IOR UART Channel A IOW TXA (or TXIRA) 64 Byte TX FIFO CS UART CHSEL Regs IR TX & RX ENDEC INTA BRG 64 Byte RX FIFO INTB RXA (or RXIRA) 8-bit Data TXRDYA Bus TXRDYB TXB (or TXIRB) UART Channel B Interface (same as Channel A) MFA RXB (or RXIRB) (OP2A , BAUDOUTA , or RXRDYA ) XTAL1 Crystal Osc/Buffer MFB XTAL2 (OP2B , CTS A/B, RI A/B, BAUDOUTB , or Modem Control Logic CD A/B, DSR A/B RXRDYB ) Reset DTR A/B, RTS A/B 2752BLK Exar Corporation 48720 Kato Road, Fremont CA, 94538 (510) 668-7000 FAX (510) 668-7017 www.exar.com XR16L2752 xr 2.25V TO 5.5V DUART WITH 64-BYTE FIFO REV. 1.2.1 FIGURE 2. PIN OUT ASSIGNMENT D5 7 39 RXA D6 8 38 TXA D7 9 37 DTRA A0 10 36 RTSA 11 35 MFA XTAL1 XR16L2752 GND 12 34 INTA 44-pin PLCC VCC XTAL2 13 33 A1 14 32 TXRDYB A2 15 31 RIB 16 30 CDB CHSEL INTB 17 29 DSRB ORDERING INFORMATION PART NUMBER PACKAGE OPERATING TEMPERATURE RANGE DEVICE STATUS XR16L2752CJ 44-Lead PLCC 0C to +70C Active XR16L2752IJ 44-Lead PLCC -40C to +85C Active 2 CS 18 6 D4 MFB 19 5 D3 IOW 20 4 D2 RESET 21 3 D1 22 GND 2 D0 RTSB 23 1 TXRDYA 24 IOR 44 VCC RXB 25 43 RIA 26 TXB 42 CDA DTRB 27 41 DSRA 28 40 CTSB CTSA