Power responsive overload sensing circuit

Claim 2

A power responsive overload sensing circuit for use with electrical signal amplifying devices including: an electrical signal amplifying device having a control electrode, a collector electrode, and an emitter electrode among a plurality of electrode connections with a first electrode connection to a first potential reference source, connection of a second electrode to a second potential reference source, and a third signal input control electrode connection; first resistive means connected between said first and second electrodes; second resistive means connected to said second electrode and in series with a load between said second electrode and said second potential reference source; load terminal means connected between said second resistive means and said second potential reference source; a voltage value threshold detector having at least two voltage level connections, with a first voltage level connection to an intermediate connection point of said first resistive means; with a second voltage level connection to said second resistive means at a connective point displaced from said second electrode connection; and with said first and second voltage level connections spanning at least a section of each of said first and second resistive means.

Claim 3

The power responsive overload sensing circuit of claim 1, wherein said third signal input control electrode of said electrical signal amplifying device is connected for receiving a signal input transmitted through signal path means from a signal source; a clamping device; said voltage value threshold detector having an output as an input connection to said clamping device; said clamping device also being provided with a connection to ground as said second potential reference source, and an output connection to said signal path means from a signal source whereby the input signal applied to said third signal input control electrode of said electrical signal amplifying device is subject to being attenuation clamped as determined by the signal level developed out of said voltage value threshold detector and applied to said clamping device.

Claim 4

The power responsive overLoad sensing circuit of claim 2, wherein said first potential reference source is a voltage power source.

Claim 5

The power responsive overload sensing circuit of claim 2, wherein said electrical signal amplifying device is a first transistor with the transistor base being said third signal input control electrode connected for receiving the input signal; with said clamping device being a second transistor having a base connection to the output of said threshold detector; the emitter-collector circuit of the second transistor being in a circuit path from said signal path means to said second potential reference source; and with said second potential reference source being ground.

Claim 6

The power responsive overload sensing circuit of claim 2, wherein a plurality of said electrical signal amplifying devices are connected in parallel to the input signal source; the said first resistive means of each electrical signal amplifying device is connected to said first voltage level connection of said threshold detector; and connection of said second voltage level connection to the second resistive means of each electrical signal amplifying device.

Claim 7

The power responsive overload sensing circuit of claim 5, wherein said first resistive means of each electrical signal amplifying device each include at least two resistors with the junction between resistors of each connected to said first voltage level connection of said threshold detector.

Claim 8

The power responsive overload sensing circuit of claim 6, wherein first and second diodes are provided in the circuit with each of said first resistive means with first like diode electrodes connected to and through one of the two resistors to said first potential reference source, the second electrode of said first diode connected to a second of the two resistors of a said first resistive means, and the second electrode of said second diode being connected to the said first voltage level connection of said voltage value threshold detector.

Claim 9

The power responsive overload sensing circuit of claim 1, wherein said first resistive means includes a first resistor and a second resistor; said second resistive means is a third resistor; with said first, second, and third resistors series connected in order from said first potential reference source to said load terminal connective means and, on through a load connected in the circuit to said second potential reference source; with said resistors so value selected that current flow through the resistors during operation develops substantially the same quantitative voltage value across said second and third resistors when the voltage developed across the load is approximately equal to one-half the voltage of said first potential reference source; and with said second and third resistors being the respective sections of said first and second resistive means spanned between said first and second voltage level connections of said voltage value threshold detector.

Claim 10

A power overload sensing and protective circuit with a series push-pull amplifier stage with substantially true power responsive protection derived from sense voltage shaping wherein: an NPN transistor and a PNP transistor have emitters interconnected by first and second series connected resistors, collectors connected to a positive voltage supply and a negative voltage supply, respectively, and with the transistor bases connected for receiving inputs from a signal source; the emitter of the NPN transistor connected through, serially third and fourth resistors to said positive voltage supply, and the common junction of said third and fourth resistors being connected through a fifth resistor to a first input connection of a threshold detector circuit; the emitter of the PNP transistor connected through, serially, sixth and seventh resistor to said negative voltage supply, and the common junction of said sixth and seventh resistors being connected through an eighth resistor to a second in connection of said threshold detector circuit; tHe first and second input connections of said threshold detector circuit being interconnected by an even number plurality of series connected diodes with anodes toward said first connection and cathodes toward said second input connection, and with a diode cathode to anode connection between the innermost of said series connected diodes; the common junction of said first and second series connected resistors and said center diode cathode to anode connection being interconnected and connected through, serially, a signal coupling capacitor and the output load to one of said power supplies; and with an output of said threshold detector circuit being connected through protection control circuitry to said signal source.

Claim 11

A power overload sensing and protective circuit with a series push-pull amplifier stage with substantially true power responsive protection derived from sense voltage shaping wherein: an NPN transistor and a PNP transistor have emitters interconnected by first and second series connected resistors, collectors connected to a positive voltage supply and a negative voltage supply, respectively, and with the transistor bases connected for receiving inputs from a signal source; the emitter of the NPN transistor connected through, serially third and fourth resistors to said positive voltage supply, and the common junction of said third and fourth resistors being connected through a fifth resistor to a first input connection of a threshold detector circuit; the emitter of the PNP transistor connected through, serially, sixth and seventh resistor to said negative voltage supply, and the common junction of said sixth and seventh resistors being connected through an eighth resistor to a second in connection of said threshold detector circuit; tHe first and second input connections of said threshold detector circuit being interconnected by an even number plurality of series connected diodes with anodes toward said first connection and cathodes toward said second input connection, and with a diode cathode to anode connection between the innermost of said series connected diodes; the common junction of said first and second series connected resistors and said center diode cathode to anode connection being interconnected and connected through, serially, a signal coupling capacitor and the output load to one of said power supplies; and with an output of said threshold detector circuit being connected through protection control circuitry to said signal source.