Current output frequency and phase comparator

Claim 2

A comparator comprising in combination: a direct current voltage source; a first source of signals; means coupled to said first source of signals for providing a first reference potential representative of signals from said first source; a signal combining circuit coupled to said direct current voltage source; a first differential amplifier coupled to said signal combining circuit for obtaining operating current from said direct current voltage source through said signal combining circuit and for creating at a junction of said signal combining circuit and said first differential amplifier an output terminal of said comparator, said first differential amplifier also having a first input terminal coupled to said first source of signals and having a second input terminal coupled to said means providing a first reference potential for comparing signals from said first source to said first reference potential; a second source of signals; switching means coupled to said second sOurce of signals and to a terminal of said signal combining circuit and responsive to said second source of signals for providing a current path for diverting said operating current from said terminal of said signal combining circuit thereby rapidly inhibiting the supply of current from said direct current voltage source to said first differential amplifier in such a manner as to rapidly turn off said first differential amplifier.

Claim 3

A comparator according to claim 1 wherein: said switching means comprises means providing a second reference potential; and a second differential amplifier coupled to said first differential amplifier, to said second source of signals, to said second reference potential and to said current path for diverting operating current from said terminal of said signal combining circuit for keying on said first differential amplifier at a predetermined threshold value of said second signals determined by said second reference potential and for rapidly keying off said first differential amplifier when said threshold value is absent from said second differential amplifier.

Claim 4

A comparator according to claim 2 wherein: said first differential amplifier comprises first and second active current conducting devices with first and second control electrodes coupled to an integrating circuit for providing as said first reference potential at said second input terminal a potential which corresponds to the average value of said signals from said first source of signals.

Claim 5

A comparator according to claim 3 wherein: said second differential amplifier comprises third and fourth active current conducting devices, a terminal of the main current conducting path of said third active current conducting device being coupled to an output terminal of said first differential amplifier and a control electrode of which is keying input terminal of said second differential amplifier for providing an output current path for said first differential amplifier when said threshold value is present on said keying input terminal; and said fourth active current conducting device has its main current conducting path coupled at one terminal to said signal combining circuit to form said current path for diverting operating current from said terminal of said signal combining circuit and at another terminal to a terminal of the main current conducting path of said third active current conducting device.

Claim 6

A comparator according to claim 4 wherein: the junction of said third and fourth active current conducting devices is coupled to a terminal of constant current regulating means, another terminal of which is coupled to a third source of reference potential for providing a path for constant current from said source of direct current voltage to said third source of reference potential in the presence or absence of said threshold value on said keying input terminal.

Claim 7

A comparator comprising: a source of direct current voltage; a signal combining circuit coupled to said source of direct current voltage; a first differential amplifier comprising first and second active current conducting devices, said first and second active current conducting devices each having one terminal of their main current conducting paths coupled to said signal combining circuit for receiving operating currents therefrom, the junction of said second device and a terminal of said signal combining circuit comprising an output terminal of said comparator, and the other terminals of the main current conducting paths of said first and second active current conducting devices being coupled to one another; a first source of signals and a first source of reference potential to be compared with one another coupled to input terminals of said first and second active current conducting devices respectively; a source of keying signals; switching means having terminals coupled to said source of keying signals and to a terminal of said signal combining circuit And responsive to said source of keying signals for providing a current path from said terminal of said signal combining circuit for diverting said operating currents from said main current conducting paths of said first and second active current conducting devices thereby rapidly turning off said first and second active current conducting devices in response to said keying signals coupled to a terminal of said switching means.

Claim 8

A comparator comprising: a source of direct current voltage; a signal combining circuit coupled to said source of direct current voltage; a first differential amplifier comprising first and second active current conducting devices, said first and second active current conducting devices each having one terminal of their main current conducting paths coupled to said signal combining circuit for receiving operating currents therefrom, the junction of said second device and a terminal of said signal combining circuit comprising an output terminal of said comparator, and the other terminals of the main current conducting paths of said first and second active current conducting devices being coupled to one another; a first source of signals and a first source of reference potential to be compared with one another coupled to input terminals of said first and second active current conducting devices respectively; a source of keying signals; switching means having terminals coupled to said source of keying signals and to a terminal of said signal combining circuit And responsive to said source of keying signals for providing a current path from said terminal of said signal combining circuit for diverting said operating currents from said main current conducting paths of said first and second active current conducting devices thereby rapidly turning off said first and second active current conducting devices in response to said keying signals coupled to a terminal of said switching means.

Claim 9

A comparator according to claim 6 wherein: said switching means comprises a second differential amplifier comprising third and fourth active current conducting devices, an input terminal of said third active current conducting device being coupled to said source of keying signals, a terminal of the main current conducting path of said third device being coupled to the common terminal of said first and second active current conducting devices and a terminal of the main current conducting path of said fourth device being coupled to said terminal of said signal combining circuit in such a manner as to divert said operating currents supplied by said signal combining circuit from said main current conducting paths of said first and second active current conducting devices through said main current conducting path of said fourth device for disabling said first differential amplifier by rapidly removing the operating currents therefrom.

Claim 10

A comparator according to claim 7 wherein: the remaining terminals of the main current conducting paths of said third and fourth devices are coupled to one another and to constant current regulating means.

Claim 11

A comparator according to claim 8 wherein: said input terminal of said second device is coupled through an integrating circuit to said input terminal of said first device to provide as said first source of reference potential coupled to an input terminal of said second device the average value of said first signals coupled to said input terminal of said first device; and said keying signal applied to said input terminal of said third device renders said third device conductive thereby preventing diversion of said operating currents from said first and second active current conducting means and providing an output current at said output terminal of said comparator representative of a comparison of said first signals applied to said input terminal of said first active current conducting device with the average value of said first signals applied to said input terminal of said second active current conducting device.

Claim 12

A comparator according to claim 9 wherein: said first, second, third, and fourth active current conducting devices are transistors; said signal combining circuit includes fifth and sixth transistors and a diode, the anode of said diode and the emitter electrode of said fifth transistor being coupled to said direct current voltage supply and the base electrode of said fifth transistor being coupled to the cathode of said diode and to the emitter electrode of said sixth transistor forming a terminal of said signal combining circuit to which a terminal of the main current conducting path of said fourth transistor is coupled to provide a terminal through which operating currents can be diverted from said first and second transistors when said fourth transistor is conductive; and the base electrode of said sixth transistor is coupled to the collector electrode of said fifth transistor and to a terminal of the main current conducting path of said first transistor for providing operating current thereto when said fourth transistor is non-conductive and the collector electrode of said sixth transistor is coupled to the collector electrode of said second transistor for providing operating current thereto and output current from said comparator when said fourth transistor is non-conductive, said junction of said collectors of said second and sixth transistors forming said output terminal of said comparator.