Precise frequency measuring analog circuit

Claim 2

A precise frequency measuring analog circuit for accurately measuring the frequency of an AC electronic signal comprising: a. first means for storing an electrical charge; b. means for charging said first storage means, said charging means responsive to positive half cycles of the AC electronic signal, said charging means charging said first storage means with a predetermined quantity of electrical charge during the positive half cycles of the AC electronic signals; c. means for switching coupled to said first storage means, said switching means being responsive to the negative half cycles of the AC electronic signal; d. second means for storing electrical charge coupled to said switching means, said second storage means receiving electrical chArge from said first storage means during the negative half cycles of the AC electronic signal; e. means for receiving electrical charge received by said second storage means, said electrical charge reception means causing substantially all the electrical charge from said first storage means to be transferred to said second storage means during the negative half cycles of the AC electronic signal; and f. means coupled to said second storage means for converting the electrical charge received by said second storage means into a voltage signal.

Claim 3

A precise frequency measuring analog circuit as recited in claim 1 wherein said charging means includes a constant voltage source for charging said first storage means.

Claim 4

A precise frequency measuring analog circuit as recited in claim 1 wherein said switching means comprises a semiconductor diode.

Claim 5

A precise frequency measuring analog circuit as recited in claim 1 wherein said switching means comprises a semiconductor diode and a transistor coupled to each other so that the cathode of said diode is connected to a base of said transistor and an emitter of said transistor is coupled to said first electrical storage means and a collector of said transistor is coupled to said second storage means.

Claim 6

A precise frequency measuring analog circuit as recited in claim 4 wherein said transistor is of the FET-type.

Claim 7

A precise frequency measuring analog circuit as recited in claim 1 wherein said first and second storage means include capacitors.

Claim 8

The precise frequency measuring device recited in claim 1 wherein said electrical charge reception means comprises a resistor coupled to said second storage means, the current through said resistor substantially equal to the electrical charge transferred per unit time to said second storage means.

Claim 9

The precise frequency measuring device of claim 1 further including amplifying means for converting the AC electronic signal into a square wave of substantially identical frequency of the AC electronic signal.

Claim 10

The precise frequency measuring device of claim 1 wherein said charge control means comprises an operational amplifier.

Claim 11

A precise frequency measuring analog circuit for accurately measuring the frequency of an electronic signal comprising: a. first means for storing an electrical charge; b. a constant voltage source for charging said first storage means; c. first switching means having a conducting and a non-conducting electrical state, said first switching means responsive to the electronic signal for establishing the state of said first switching means, said first switching means coupled between said first storage means and said constant voltage source for charging with a predetermined quantity of electrical charge said first storage means when said first switching means is in the conducting state; d. second means for storing electrical charge; e. second switching means having a conducting and a non-conducting electrical state, said second switching means responsive to the electronic signal for changing the state of conduction of said second switching means, said second switching means coupled between said second storage means and said first storage means, said second switching means being in the non-conducting state when said first switching means is in the conducting state and vice-versa; f. an operational amplifier coupled to said second storage means for transferring charge substantially equal to the predetermined electronic charge of said first storage means to said second storage means each time said second switching means is switched to the conducting state; and g. conversion means coupled to said second storage means for converting electrical charge received by said second capacitor means into an electrical voltage, said electrical voltage being determined by a rate of transfer of the predetermined charge quantities to said second storage means.

Claim 12

A precise frequency measuring analog circuit for accurately measuring the frequency of an electronic signal comprising: a. first means for storing an electrical charge; b. a constant voltage source for charging said first storage means; c. first switching means having a conducting and a non-conducting electrical state, said first switching means responsive to the electronic signal for establishing the state of said first switching means, said first switching means coupled between said first storage means and said constant voltage source for charging with a predetermined quantity of electrical charge said first storage means when said first switching means is in the conducting state; d. second means for storing electrical charge; e. second switching means having a conducting and a non-conducting electrical state, said second switching means responsive to the electronic signal for changing the state of conduction of said second switching means, said second switching means coupled between said second storage means and said first storage means, said second switching means being in the non-conducting state when said first switching means is in the conducting state and vice-versa; f. an operational amplifier coupled to said second storage means for transferring charge substantially equal to the predetermined electronic charge of said first storage means to said second storage means each time said second switching means is switched to the conducting state; and g. conversion means coupled to said second storage means for converting electrical charge received by said second capacitor means into an electrical voltage, said electrical voltage being determined by a rate of transfer of the predetermined charge quantities to said second storage means.