LMS1485  Product Folder

The LMS1485 is a low power differential bus/line transceiver designed for high speed bidirectional data communication on multipoint bus transmission lines. It is designed for balanced transmission lines. It meets ANSI Standards TIA/EIA RS422-B, TIA/EIA RS485-A and ITU recommendation and V.11 and X.27.

The LMS1485 combines a TRI-STATE™ differential line driver and differential input receiver, both of which operate from a single 5.0V power supply. The driver and receiver have an active high and active low, respectively, that can be externally connected to function as a direction control. The driver and receiver differential inputs are internally connected to form differential input/output (I/O) bus ports that are designed to offer minimum loading to bus whenever the driver is disabled or when V_CC = 0V. These ports feature wide positive and negative common mode voltage ranges, making the device suitable for multipoint applications in noisy environments.

The LMS1485 is build with National's advanced BiCMOS process and is available in a 8-Pin SOIC package. It is a drop-in socket replacement to ADI's ADM1485 and LTC's LT1485.

• Meet ANSI standard RS-485-A and RS-422-B
• Data rate 30Mbps
• Single supply voltage operation, 5V
• Wide input and output voltage range
• Thermal shutdown protection
• Short circuit protection
• Driver propagation delay 10ns
• Receiver propagation delay 25ns
• High impedance outputs with power off
• Open circuit fail-safe for receiver
• Extended operating temperature range -40°C to 85°C
• ESD rating 8kV HBM
• Drop-in replacement to ADM1485 and LT1485
• Available in 8-pin SOIC
• Low supply current, I_CC = 1mA

• Low power RS-485 systems
• Network hubs, bridges, and routers
• Point of sales equipment (ATM, barcode scanners,...)
• Local area networks (LAN)
• Integrated service digital network (ISDN)
• Industrial programmable logic controllers
• High speed parallel and serial applications
• Multipoint applications with noisy environment