XR16L2450 Datasheet | Exar

DESCRIPTION The XR16L2450 (L2450) is a dual universal asynchronous receiver and transmitter (UART). The XR16L2450 is an improved version of the ST16C2450 with lower operating voltage and 5 volt tolerant inputs. The L2450 provides enhanced UART functions, a modem control interface and data rates up to 1.5 Mbps. Onboard status registers provide the user with error indications and operational status. Independent programmable baud rate generators are provided to select transmit and receive clock rates up to 1.5 Mbps. An internal loopback capability allows onboard diagnostics. The L2450 is available in a 44pin PLCC and 48-pin TQFP packages. The L2450 is fabricated in an advanced CMOS process capable of operating from 2.25 volt to 5.5 volt power supply with 5 volt tolerant inputs. APPLICATIONS FEATURES - 2.25 to 5.5 Volt Operation - 5 Volt Tolerant Inputs - Pin-to-pin patible to Exar’s ST16C2450, ST16C2550, XR16C2850 TQFP package XR16L2550, XR16L2750 and - Pin-to-pin patible to TI’s TL16C752B on the 48- 2 independent UART channels - - - - - - - Portable Appliances - Telemunication Network Routers - Ethernet Network Routers - Cellular Data Devices - Factory Automation and Process Controls FIGURE 1. XR16L2450 BLOCK DIAGRAM Up to 1.5 Mbps data rate with a 24 MHz crystal oscillator or external clock frequency 1 byte Transmit FIFO 1 byte Receive FIFO with error tags Status report registers Modem control signals (CTS#, RTS#, DSR#, DTR#, RI#, CD#) Programmable character lengths (5, 6, 7, 8) with even, odd, or no parity - Crystal oscillator or external clock input - TTL patible inputs, outputs - Industrial temperature ranges - 48-TQFP and 44-PLCC packages - 5V Tolerant inputs 2.25 to 5.5 Volt VCC A2:A0 D7:D0 IOR# IOW# CSA# CSB# INTA INTB 8-bit Data Bus Interface UART Channel A UART Regs THR RHR Modem I/Os TXA RXA RTSA#, CTSA#, DTRA#, DSRA#, CDA#, RIA#, OP2A# TXB RXB RTSB#, CTSB#, DTRB#, DSRB#, CDB#, RIB#, OP2B# XTAL1 XTAL2 UART Channel B (same as Channel A) Reset...