SP337E 3.3V TO 5V RS-232/RS-485/RS-422 MULTIPROTOCOL TRANSCEIVER MARCH 2011 REV. 1.0.2 GENERAL DESCRIPTION FEATURES The SP337E is a dual mode serial transceiver containing both RS-232 and RS-485/422 line drivers 3.3V to 5V Single Supply Operation and receivers. The RS-232 mode provides three Robust +/-15kV ESD Protection drivers and five receivers to support all eight signals commonly used in the DB9 serial port connector Human Body Model (3TX/5RX). In RS-485 mode the device features two Max Data Rate of 15Mbps in RS-485 mode independent high speed RS-485/422 transmit and and up to 1Mbps in RS-232 mode (SP337EU) receive channels (2TX/2RX). The default RS-485 configuration is full-duplex, but half-duplex operation 3 Drivers, 5 Receivers RS-232/V.28 can be obtained by tying together the TX and RI pins, 2 Drivers, 2 Receivers RS-485/RS-422 and the TXEN and RXEN signals. Full-Duplex Configuration The SP337E is pin compatible to Exars SP334. 1/8th Unit Load, up to 256 receivers on bus The SP337EB features a maximum data rate of RS-485 Advanced Failsafe on Open, Short or 250kbps in RS-232 mode and a maximum data rate Terminated Lines of 15Mbps in RS-485. However, the SP337EU features a maximum data rate of 1Mbps in RS-232 Full Differential Driver Tri-State (Hi-Z) Control mode and a maximum data rate of 15Mbps in RS-485 Receiver Output Tri-State Control mode. WSOIC-28 or TSSOP-28 Package The Exar-patented high efficiency charge pumps (5,306,954) deliver true RS-232 driver output voltages from a single power supply from 3.3V to 5V. TYPICAL APPLICATIONS Charge pump outputs are self-monitored to minimize power consumption. The SP337E requires only four Dual Protocol Serial Ports (RS-232 or RS-485) 0.1F capacitors for complete functionality. Industrial Computers All RS-485 receivers or transceivers feature high Industrial and Process Control Equipment impedance inputs which allow up to 256 transceivers on a single shared bus. When configured in RS-485 Point-Of-Sales Equipment mode, each driver may be individually enabled or put Networking Equipment into tri-state, simplifying use on shared buses or for bidirectional communication. The RS-485/422 drivers HVAC Controls Equipment can be disabled (high-Z output) by the TXEN enable Building Security Equipment pin. The RS-232 receiver outputs can be disabled by the RXEN enable pin. All receivers have advanced failsafe protection to prevent oscillation when inputs are un-connected. In RS-232 mode, each receiver input has a 5k pull- down to ground. in RS-485 mode, receivers will default to output logic 1 if inputs are floating, shorted, or open but terminated. All driver outputs and receiver inputs are protected against ESD strikes up to +/-15,000 volts. Exar Corporation 48720 Kato Road, Fremont CA, 94538 (510) 668-7000 FAX (510) 668-7017 www.exar.com SP337E 3.3V TO 5V RS-232/RS-485/RS-422 MULTIPROTOCOL TRANSCEIVER REV. 1.0.2 FIGURE 1. TYPICAL RS-232 AND RS-485 APPLICATION CIRCUITS ORDERING INFORMATION OPERATING TEMPERATURE PART NUMBER PACKAGE DEVICE STATUS RANGE SP337EBCT-L 28-pin WSOIC 0C to +70C Active SP337EBCY-L 28-pin TSSOP 0C to +70C Active SP337EBET-L 28-pin WSOIC -40C to +85C Active SP337EBEY-L 28-pin TSSOP -40C to +85C Active SP337EUCT-L 28-pin WSOIC 0C to +70C Active SP337EUCY-L 28-pin TSSOP 0C to +70C Active SP337EUET-L 28-pin WSOIC -40C to +85C Active SP337EUEY-L 28-pin TSSOP -40C to +85C Active 2