ST491A Datasheet | STMicroelectronics

DESCRIPTION The ST491A is a low power transceiver for RS-485 and RS-422 munications. The device contains one driver and one receiver in full duplex configuration. The ST491A draws 5m A (typ.) of supply current when unloaded and operates from a single 5V supply. ORDERING CODES Type ST491ACN ST491ABN ST491ACD ST491ABD ST491ACDR ST491ABDR Temperature Range 0 to 70 °C -40 to 85 °C 0 to 70 °C -40 to 85 °C 0 to 70 °C -40 to 85 °C Package Driver is short-circuit current limited and is protected against excessive power dissipation by thermal shutdown circuitry that place the driver outputs into a high-impedance state. The receiver input has a fail-safe feature that guarantees a logic high output if both inputs are open circuit. ments 25parts per tube / 40tube per 25parts per tube / 40tube per 50parts per tube / 20tube per 50parts per tube / 20tube per 2500 parts per reel 2500 parts per reel box box box box DIP-14 DIP-14 SO-14 (Tube) SO-14 (Tube) SO-14 (Tape & Reel) SO-14 (Tape & Reel) July 2003 1/12 PIN CONFIGURATION PIN DESCRIPTION Pl N N° 1 2 3 4 5 6 7 8 9 10 11 12 13 14 SYMBOL NC RO RE DE DI GND GND NC Y Z B A NC VCC NAME AND FUNCTION Not Connected Receiver Output. Receiver Output Enable Driver Output Enable Inverting Driver Input. Ground Ground Not Connected Non-inverting Driver Output Inverting Driver Output Inverting Receiver Input Non-inverting Receiver Input Not Connected Supply Voltage TRUTH TABLE (DRIVER) INPUT DI L H X DE H H L Y L H Z OUTPUTS Z H L Z TRUTH TABLE (RECEIVER) INPUT A-B ≥ -0.2V between -0.2V to 0.2V ≤ -0.2V OPEN X RE L L L L H OUTPUT RO H ? L H Z X= Don’t Care; Z=High Impedance ?= Irrelevant; X= Don’t Care; Z=High Impedance 2/12 ABSOLUTE MAXIMUM RATINGS Symbol VCC VDI VY, VZ VA, VB VRO ESD Supply Voltage Driver Input Voltage Driver Output Voltage Receiver Input Voltage Receiver Output Voltage Human Body Model Parameter Value 7 -0.5 to 7 -7.5 to 12.5 -7.5 to 12.5 -0.3 to (VCC + 0.3) 3.5 Unit V V V V V KV Absolute Maximum...