Signal amplification circuit with phase detecting means and variable signal level recognition means

Claim 2

A circuit for generating an electrical signal having a predetermined phase relationship with respect to an input signal comprising: comparator means having first and second input terminal means and an output terminal means; input signal means communicating with said first input terminal means for applying a voltage signal thereto representative of the input signal; reference signal means communicating with said second input terminal means for generating a reference voltage signal; source means communicating with said reference signal means operative to establish a steady state level of reference voltage signal which differs from the voltage applied to said first input terminal means by said input signal means under nonsignal conditions by a preselected amount; detecting means communicating with said input signal means and coupled to said reference signal means operative to controllably vary the reference voltage signal in response to the immediately preceding input signal; said comparator means operative to generate an output having first and second signal levels, said first signal level being indicative of the occurrence of an input signal and switchable between said first and second signal levels in response to the voltage signal at said first terminal means changing its electrical relationship with respect to the voltage signal at said second terminal means; and switching means communicating with said output terminal means and responsive to the first signal level operative to controllably switch the reference voltage signal to a preselected value.

Claim 3

The circuit of claim 1 wherein said switching means are operative to controllably switch the reference voltage level to a value substantially equal to the level of the input signal means voltage signal under nonsignal conditions whereby the output of the comparator means may switch from the first signal level to the second signal level in response to the zero crossing of the input signal.

Claim 4

The circuit of claim 1 wherein said detecting means include means responsive to the peak magnitude of the immediately preceding input signal for controllably increasing the reference voltage signal.

Claim 5

The circuit of claim 3 wherein the detecting means further include decay means for reducing the reference voltage signal from the increased value to its steady state level in a predetermined manner.

Claim 6

The circuit of claim 3 wherein the reference signal means comprise impedance means and the detecting means comprise a controlled current source means operative to generate a current having an initial magnitude responsive to the peak magnitude of the immediately preceding input signal and means for communicating this current to the reference signal impedance means.

Claim 7

The circuit of claim 5 wherein said switching means are further operative to shunt said controlled current source current away from said reference signal impedance means when the comparator means output is at the first level whereby the controlled current source current will not affect switching of the compaRator output from the first level to the second level but may contribute to subsequent switching of the comparator output from the second level to the first level.

Claim 8

The circuit of claim 6 including further pulse generator means responsive to said comparator means output switching from said first level to said second level operative to generate in response thereto a pulse having a predetermined pulse duration.

Claim 9

A circuit for generating an electrical signal having a predetermined phase relationship with respect to an input signal comprising: first and second current source means; input signal impedance means receiving said first current and generating a voltage signal having a steady state nonsignal value and an A.C. signal component having a first occurring peak value and a succeeding inverted peak value; reference signal impedance means receiving said second current and generating a voltage signal having a first reference level; said first and second currents, said input signal impedance means and said reference signal impedance means cooperative to provide a reference voltage signal value which is approximately equal to the steady state nonsignal value but intermediate said nonsignal value and a first occurring peak value; comparator means having an output terminal and a pair of input terminals, each of which receives one of said reference voltage signal and said input voltage signal operative to generate a first level of output signal when said input signal exceeds said reference signal and a econd level of output signal when said reference signal exceeds the input signal; switching means responsive to one of said first and second levels of output signal operative to controllably alter said reference voltage signal to change said reference voltage signal to a value substantially equal to the steady state non-signal value whereby switching from one of said first and second levels of output signal to the other can be accomplished in response to a zero crossing of the A.C. component of the input signal; and controlled current source means communicating with said input impedance means operative to generate a current having a magnitude related to the first occurring peak value of the immediately preceding input signal A.C. component and conductor means for applying this controlled current to said reference impedance means whereby the reference voltage value may be controllably varied in the direction of the immediately preceding first occurring peak value.

Claim 10

A circuit for generating an electrical signal having a predetermined phase relationship with respect to an input signal comprising: first and second current source means; input signal impedance means receiving said first current and generating a voltage signal having a steady state nonsignal value and an A.C. signal component having a first occurring peak value and a succeeding inverted peak value; reference signal impedance means receiving said second current and generating a voltage signal having a first reference level; said first and second currents, said input signal impedance means and said reference signal impedance means cooperative to provide a reference voltage signal value which is approximately equal to the steady state nonsignal value but intermediate said nonsignal value and a first occurring peak value; comparator means having an output terminal and a pair of input terminals, each of which receives one of said reference voltage signal and said input voltage signal operative to generate a first level of output signal when said input signal exceeds said reference signal and a econd level of output signal when said reference signal exceeds the input signal; switching means responsive to one of said first and second levels of output signal operative to controllably alter said reference voltage signal to change said reference voltage signal to a value substantially equal to the steady state non-signal value whereby switching from one of said first and second levels of output signal to the other can be accomplished in response to a zero crossing of the A.C. component of the input signal; and controlled current source means communicating with said input impedance means operative to generate a current having a magnitude related to the first occurring peak value of the immediately preceding input signal A.C. component and conductor means for applying this controlled current to said reference impedance means whereby the reference voltage value may be controllably varied in the direction of the immediately preceding first occurring peak value.

Claim 11

A circuit for generating an electrical signal having a predetermined phase relationship with respect to an input signal comprising first and second current source means; input signal impedance means receiving said first current and generating a voltage signal having a steady state nonsignal value and an A.C. signal component having a first occurring peak value and a succeeding inverted peak value; reference signal impedance means receiving said second current and generating a voltage signal having a first reference level; said first and second currents, said input signal impedance means and said reference signal impedance means cooperative to provide a reference voltage signal value which is approximately equal to the steady state nonsignal value but intermediate said nonsignal value and a first occurring peak value; comparator means having an output terminal and a pair of input terminals, each of which receives one of said reference voltage signal and said input voltage signal operative to generate a first level of output signal when said input signal exceeds said reference signal and a second level of output signal when said reference signal exceeds the input signal; and switching means responsive to one of said first and second levels of output signal operative to controllably alter said reference voltage signal to change said reference voltage signal to a value substantially equal to the steady state nonsignal value whereby swiTching from one of said first and second levels of output signal to the other can be accomplished in response to a zero crossing of the A.C. component of the input signal; said switching means including shunt impedance means which are electrically coupled in electrical parallel relation with said reference impedance means when the output of the comparator means is at a first level and are electrically removed from parallel relation with said reference impedance means when said comparator output is at a second level.

Claim 12

A circuit for generating an electrical signal having a predetermined phase relationship with respect to an input signal comprising first and second current source means; input signal impedance means receiving said first current and generating a voltage signal having a steady state nonsignal value and an A.C. signal component having a first occurring peak value and a succeeding inverted peak value; reference signal impedance means receiving said second current and generating a voltage signal having a first reference level; said first and second currents, said input signal impedance means and said reference signal impedance means cooperative to provide a reference voltage signal value which is approximately equal to the steady state nonsignal value but intermediate said nonsignal value and a first occurring peak value; comparator means having an output terminal and a pair of input terminals, each of which receives one of said reference voltage signal and said input voltage signal operative to generate a first level of output signal when said input signal exceeds said reference signal and a second level of output signal when said reference signal exceeds the input signal; and switching means responsive to one of said first and second levels of output signal operative to controllably alter said reference voltage signal to change said reference voltage signal to a value substantially equal to the steady state nonsignal value whereby swiTching from one of said first and second levels of output signal to the other can be accomplished in response to a zero crossing of the A.C. component of the input signal; said switching means including shunt impedance means which are electrically coupled in electrical parallel relation with said reference impedance means when the output of the comparator means is at a first level and are electrically removed from parallel relation with said reference impedance means when said comparator output is at a second level.

Claim 13

The circuit of claim 9 wherein said switching means comprise a solid state electronic switch means responsive to said output signal operative to establish a current flow path therethrough upon the occurrence of one of said first and second levels of output signal and operative to terminate the current flow path upon the occurrence of the other of said first and second levels of output signal and shunt impedance means interconnecting said reference signal impedance means and said electronic switch means, said shunt impedance means and said electronic switch means being electrically connected in parallel with said reference signal impedance means.