Low input current, high gain optocoupler. high gain series couplers use a light emitting diode and an integrated high gain photodetector to provide extremely high current transfer ratio between input and output. Suitable for use in ground isolate most logic families - TTL/TTL, CMOS/TTL, CMOS/CMOS, LSTTL/TTL, CMOS/LSTTL, low input current line receiver, EIA RS-232C line receiver, telephone ring detector, 117V ac line voltage status indicator - low input power dissipation, Low power systems - ground isolation applications.