Electronic ring monitoring device for telecommunications line

摘要

An electronic ring monitoring device is disclosed that includes telecommunications interface circuitry, ring detection circuitry, isolation circuitry, and output driver circuitry. The telecommunications interface circuitry may include a switch allowing programmable selection of alternate connections to the telecommunications source depending upon the particular source involved. The ring detection circuitry may include a bridge rectifier, a filtering capacitor, a bleeder resistor to prevent false detection from stray voltages on the telecommunications line, and a variable resistor to allow a programmable detection level. The isolation circuitry may include a optical isolator that will electronically isolate the telecommunications side of the device from the output side of the device. The driver circuitry may include a triac that allows current flow when a ring is indicated and may include inductive load protection circuitry.