DESCRIPTION

The 485ELC is low capacitance, two-stage transient voltage protector the provides primary and secondary protecton against lightning, inductve switching and electrostatc discharge (ESD) transient threats. The frst stage diverts the transient current through the ground terminal return path and the second stage clamps the voltage to a safe level without interrupton of service.

The 485ELC is designed to protect data lines, transmission lines, tming and control interface circuits from common mode (line-to-ground) or di?erental (line-line) transients. Terminals 1 & 2 and 3 & 4 are designed as line pairs. A transient voltage suppressor is connected across each line pair for di?erental mode protecton.

Capacitance over the operatng voltage range is important. If capacitance is non-linear, distorton, loss of data or access to the I/O port can occur (See Figure 1).

FEATURES

? Compatble with IEC 61000-4-2 (ESD): Air - 15kV, Contact - 8kV

? Compatble with IEC 61000-4-4 (EFT): 40A - 5/50ns

? Compatble with IEC 61000-4-5 (Surge): 95A, 8/20μs, Level 4 (Line Gnd) & 48A, Level 4 (Line-Line)

? Low Capacitance - 25pF

? Designed for EIA Standard RS-485 Data Lines

? Permanent Two-Stage 2 Line Pair Protector

? Subnanosecond Response Time

? Common & Di?erental Mode Protecton

? Automatc Reset - Does Not Interrupt Service

? E?ectve Against Lightning, Inductve Switching and ESD

APPLICATIONS

? Ethernet & Catagory 5 Systems

? RS-485 Serial Communicaton Lines

? ISDN Equipment/Systems

? Video Transmission Systems

? Smoke Detector & Fire Alarm Systems