Dual current limiting voltage regulator

Claim 1

The current sensing control device for producing a control signal for application to a overvoltage protection circuit for a generator comprising: resistor means adapted to be connected between said generator and a load to be protected for developing a voltage representing generator output current; a proportional control means including first and second proportionally and complementally conducting transistors, first means connecting one side of said resistor means to the first of said complemental transistors to establish a bias therefor, second means including at least a first voltage forming circuit element connecting the other side of said resistor means to the second of said complemental transistors to provide a variable bias to said second transistor to cause said second transistor to conduct increasingly from a first threshold value over a predetermined range; a third proportionally conducting transistor connected between said first and second transistors for developing a control signal which varies in magnitude according to the relative conductances of said first and second transistors; means connecting the control signal to an overvoltage protection circuit; a second voltage forming circuit element; and switch means for selectively connecting said second voltage forming circuit element in and out of circuit with said first voltage forming circuit element to vary the threshold point of conductance of said second transistor.