INTEGRATED CIRCUIT MICROPROCESSOR-CONTROLLED TELEPHONE TWO WIRE/FOUR WIRE TRANSMISSION CIRCUIT, AND LINE CURRENT SAFEGUARD POWERING

摘要

The telephone circuit of the invention comprises a transmission circuit short-circuited during decimal numbering by an active circuit when the handset is lifted or during the emission of a decimal numbering digit, the line current supplying, through a voltage stabilizing circuit and a voltage regulation circuit, the microprocessor controlling the telephone circuit.