Circuit arrangement for feeding modules in user stations

Claim 2

A circuit arrangement for feeding a module containing a component requiring a constant operating voltage in a user station fed by a current-conducting connection path, comprising: current control means connected for controlling the current in said connection path; resistance control means connected for controlling the alternating current resistance presented by said circuit arrangement to said connection path; means defining a first current conducting branch connected for feeding current supplied by said connection path to said module; and means defining a second current conducting branch connected for conducting current supplied by said connection path in a manner to bypass said module only when the voltage between two selected points in said connection path falls below the constant operating voltage required by the module.

Claim 3

Circuit arrangement as defined in claim 1 wherein: said connection path presents two terminals between which flows the current in said connection path; said current control means comprise a first transistor of one conductivity type having a feedback-connected emitter, an emitter resistor connected between said emitter of said first transistor and one of said terminals, a voltage divider connected between said two terminals and having a tap connected to the base of said first transistor, and a second transistor of the opposite conductivity type having its collector-base path connected in parallel with the collector-emitter path of said first transistor to form with said first transistor a complementary Darlington circuit, with the emitter of said second transistor being arranged to be connected to the module; said resistance control means comprise a resistor and a capacitor connected together in series between said one terminal and said voltage divider tap; said means defining a first current conducting branch includes said Darlington circuit; and said means defining a second current conducting branch comprise a third transistor of said opposite conductivity type having its emitter-collector path connected between the emitter of said first transistor and the other one of said terminals, a fourth transistor of said one conductivity type having its emitter-collector path connected between the base of said third transistor and the collector of said first transistor, a fifth transistor of said opposite conductivity type having its emitter-collector path connected between the emitter of said first transistor and the base of said fourth transistor and having its base connected to the base of said first transistor, and a second resistor connected between the base of said fourth transistor and said one of said terminals.

Claim 4

Circuit arrangement as defined in claim 1 wherein said means defining a second current conducting branch comprise voltage responsive switching means connected for controlling the conductive state of the second branch.