xr ST16C2450 2.97V TO 5.5V DUART MAY 2005 REV. 4.0.1 FEATURES GENERAL DESCRIPTION The ST16C2450 (2450) is a dual universal asynchro- Added feature in devices with top markingA2 nous receiver and transmitter (UART). The YYW and newer: ST16C2450 is an improved version of the 5 Volt Tolerant Inputs ST16C2450 with lower operating voltage and 5 volt 2.97 to 5.5 Volt Operation tolerant inputs. The 2450 provides enhanced UART Pin-to-pin compatible to Exars XR16C2450, functions, a modem control interface and data rates up to 1.5 Mbps. Onboard status registers provide the ST16C2550, XR16L2550, XR16L2750 and user with error indications and operational status. In- XR16C2850 dependent programmable baud rate generators are 2 independent UART channels provided to select transmit and receive clock rates up Up to 1.5 Mbps data rate with a 24 MHz crystal to 1.5 Mbps. An internal loopback capability allows oscillator or external clock frequency onboard diagnostics. The 2450 is available in a 44- 1 byte Transmit FIFO pin PLCC and 48-pin TQFP packages. The 2450 is 1 byte Receive FIFO with error tags fabricated in an advanced CMOS process capable of operating from 2.97 volt to 5.5 volt power supply. The Status report registers devices with a top marking ofA2 YYW or newer Modem control signals (CTS , RTS , DSR , have 5 volt tolerant inputs. DTR , RI , CD ) Programmable character lengths (5, 6, 7, 8) APPLICATIONS with even, odd, or no parity Portable Appliances Crystal oscillator or external clock input Telecommunication Network Routers TTL compatible inputs, outputs Ethernet Network Routers Industrial temperature ranges Cellular Data Devices 48-TQFP and 44-PLCC packages Factory Automation and Process Controls FIGURE 1. ST16C2450 BLOCK DIAGRAM 2.97 to 5.5 Volt VCC *5V Tolerant inputs A2:A0 D7:D0 UART Channel A TXA IOR THR IOW UART Regs RHR RXA CSA CSB RTSA , CTSA , Modem I/Os 8-bit Data INTA DTRA , DSRA , BRG Bus CDA , RIA , OP2A INTB Interface TXB RXB UART Channel B RTSB , CTSB , (same as Channel A) DTRB , DSRB , Reset CDB , RIB , OP2B XTAL1 Crystal Osc/Buffer XTAL2 Exar Corporation 48720 Kato Road, Fremont CA, 94538 (510) 668-7000 FAX (510) 668-7017 www.exar.com ST16C2450 xr 2.97V TO 5.5V DUART REV. 4.0.1 FIGURE 2. PIN OUT ASSIGNMENT RESET D5 1 36 DTRB D6 2 35 DTRA D7 3 34 RTSA RXB 4 33 5 32 OP2A RXA ST16C2450 NC 6 31 NC 48-pin TQFP TXA 7 30 INTA TXB 8 29 INTB VCC D0 1 40 OP2B 9 28 A0 D1 2 39 RIA CSA 10 27 A1 D2 3 38 CDA CSB 11 26 A2 D3 4 37 DSRA NC 12 25 NC D4 5 36 CTSA D5 6 35 RESET D6 7 34 DTRB D7 8 33 DTRA RXB 9 32 RTSA RXA 10 31 OP2A TXA 11 30 INTA TXB 12 29 INTB 7 39 RESET D5 OP2B 13 28 A0 D6 8 38 DTRB CSA 14 27 A1 D7 9 37 DTRA RXB 10 36 RTSA CSB 15 26 A2 RXA 11 35 OP2A XTAL1 16 25 CTSB ST16C2450 NC 12 34 NC XTAL2 17 24 RTSB 44-pin PLCC TXA 13 33 INTA IOW 18 23 RIB TXB 14 32 INTB CDB 19 22 DSRB OP2B 15 31 A0 GND 20 21 IOR CSA 16 30 A1 CSB 17 29 A2 ORDERING INFORMATION OPERATING PART NUMBER PACKAGE TEMPERATURE DEVICE STATUS RANGE ST16C2450CP40 40-Lead PDIP 0C to +70C Active. See the ST16C2450CQ48 for new designs. ST16C2450CJ44 44-Lead PLCC 0C to +70C Active ST16C2450CQ48 48-Lead TQFP 0C to +70C Active ST16C2450IP40 40-Lead PDIP -40C to +85C Active. See the ST16C2450IQ48 for new designs. ST16C2450IJ44 44-Lead PLCC -40C to +85C Active ST16C2450IQ48 48-Lead TQFP -40C to +85C Active 2 ST16C2450CP40 XTAL1 48 13 D4 XTAL1 18 6 D4 XTAL2 14 47 D3 XTAL2 19 5 D3 IOW 15 46 D2 20 IOW 4 D2 CDB 45 D1 16 CDB 21 3 D1 GND 17 44 D0 22 GND 2 D0 NC 18 43 NC NC 23 1 NC IOR 19 42 VCC IOR 24 44 VCC DSRB 20 41 RIA DSRB 25 43 RIA RIB 21 40 CDA RTSB RIB 26 42 CDA 22 39 DSRA CTSB 38 27 23 CTSA RTSB 41 DSRA NC 24 37 NC CTSB 28 40 CTSA