Back to results
US 4,063,149 AGranted
Current regulating circuits
AssigneeRCA Corporation
InventorBrian Crowle
Life of this patent
Estimating the term…
Abstract
Two current amplifiers are connected in a regenerative feedback loop. One of them exhibits an exponential decrease in current gain in response to a linear increase in input current, in consequence of which the current level in the loop stabilizes at a predictable level.
Claims11
A current regulating circuit comprising:
- a first current amplifier, having input and output circuits and exhibiting a current gain between its input and output circuits which tends to decrease exponentially with increasing current in its input circuit;
- and
- a second current amplifier having an input circuit to which the output circuit of said first current amplifier is direct coupled and having an output circuit direct coupled to the input circuit of said first current amplifier, thereby to form a loop connection of said first and said second current amplifiers, and exhibiting a current gain between its input and output circuits of a sense which causes said loop connection to be regenerative in nature and of an amplitude which causes current levels in the loop to tend to increase until predetermined levels are achieved whereat the current gain of the loop is reduced to unity.
A current regulating circuit for maintaining a constant current between first and second terminals comprising:
- first and second current amplifiers each having an input terminal, an output terminal and a common terminal, said first and said second current amplifiers respectively exhibiting monotonically increasing and monotonically decreasing current gains as the current levels in said current amplifier increase;
- a first direct current conductive path between said first terminal and the common terminal of said first current amplifier;
- a second direct current conductive path between said second terminal and the common terminal of said second current amplifier;
- a third direct current conductive path between the output terminal of said first current amplifier and the input terminal of said second current amplifier;
- and
- a fourth direct current conductive path between the output terminal of said second current amplifier and the input terminal of said first current amplifier, said third and said fourth conductive paths connecting said first and said second current amplifiers in a regenerative feedback loop.
3 more elements
A current regulating circuit comprising, in combination:
- a. a first current amplifier having an input and an output terminal and means for establishing a predictably predetermined current gain of -G between its said input and output terminals, G being positive valued, and
- b. a second current amplifier having an input terminal to which the output terminal of said first current amplifier is direct coupled, having an output terminal direct coupled to the input terminal of said first current amplifier, having a common terminal for connection to a point of reference potential, having first and second transistors of similar conductivity type each with base and emitter and collector electrodes, having a resistance with first and second ends connected respectively to said first transistor base electrode and to said second transistor base electrode, and galvanically coupled respectively to the input terminal of said second current amplifier and to said first transistor collector electrode, having direct connections of the emitter electrodes of said first and second transistors to its said common terminal for imposing the same emitter potentials on said first and second transistors, and having a galvanic coupling of said second transistor collector electrode to its said output terminal.
A current regulating circuit comprising:
- first and second terminals for application of an operating potential therebetween;
- a current mirror amplifier having input and output terminals between which a constant current gain -G is exhibited and having a common terminal connected to said first terminal;
- a resistance having a first end to which the output terminal of said current mirror amplifier is galvanically coupled and having a second end;
- first and second transistors of similar conductivity type, having respective emitter electrodes directly connected to said second terminal so as to be held at the same potential, having respective base electrodes connected respectively to the first end of said resistance and to the second end of said resistance, and having respective collector electrodes galvanically coupled respectively to the second end of said resistance and to the input terminal of said current amplifier.
1 more element
Dependencies are inferred from the claim text.