Pulse detection circuit using amplitude and time qualification

Claim 2

A pulse detection circuit comprising: means for detecting peaks in an input signal and producing a peak detect signal when a peak is detected; means for comparing said input signal to a threshold level; means, coupled to said means for detecting and said means for comparing, for producing an amplitude qualified peak output signal when a peak is detected above said threshold level; and means, having an input coupled to said means for producing an amplitude qualified peak output signal, and said means for detecting peaks, for producing a time qualified peak signal at an output after a predetermined delay from said amplitude qualified output signal if said peak detect signal is still present after said delay, said means for producing a time qualified peak signal being nonresponsive to signals at said input during said delay.

Claim 3

The apparatus of claim 1 wherein said means for detecting peaks includes a differentiator coupled to receive said input signal and a zero-crossing comparator coupled to an output of said differentiator, an output of said comparator producing said peak detect signal.

Claim 4

The apparatus of claim 2 wherein said input signal is a differential signal coupled across first and second input lines and said means for comparing includes a negative threshold comparator having a first input coupled to a first one of said input lines and a second input coupled to a first threshold voltage and a positive threshold comparator having a first input coupled to a second one of said input lines and a second input coupled to a second threshold voltage.

Claim 5

The apparatus of claim 3 wherein said means for producing a qualified peak output signal is a latching flip-flop having a data input coupled to a positive output of said zero-crossing comparator and further comprising: a first AND gate having a first input coupled to an output of said negative threshold comparator and a second input coupled to a positive output of said zero-crossing comparator; a second AND gate having a first input coupled to an output of said positive threshold comparator and a second input coupled to a negative output of said zero-crossing comparator; an OR gate having first and second inputs coupled to outputs of said negative and positive threshold comparators, respectively, and an output coupled to a clock input of said flip-flop.

Claim 6

The apparatus of claim 4 wherein said means for producing a time qualified peak signal comprises a one-shot delay circuit coupled between said OR gate output and said clock input of said flip-flop.

Claim 7

The apparatus of claim 1 further comprising a pre-amplifier and a filter for conditioning said input signal and presenting said input signal to said means for detecting peaks.

Claim 8

The apparatus of claim 1 wherein said means for producing a time qualified peak signal comprises: a one-shot delay circuit having an input coupled to said means for producing an amplitude qualified peak output signal; and a flip-flop having one input coupled to said means for detecting peaks and another inut coupled to an output of said one-shot delay circuit.

Claim 9

A pulse detection circuit comprising: a differentiator coupled to receive an input signal, said input signal being a differential signal coupled across first and second input lines; a zero-crossing comparator coupled to an output of said differentiator; a negative threshold comparator having a first input coupled to a first one of said input lines and a second input coupled to a first threshold voltage; a positive threshold comparator having a first input coupled to a second one of said input lines and a second input coupled to a second threshold voltage; a first AND gate having a first input coupled to an output of said negative threshold comparator and a second input coupled to a positive output of said zero-crossing comparator; a second AND gate having a first input coupled to an output of said positive threshold comparator and a second input coupled to a negative output of said zero-crossing comparator; an OR gate having first and second inputs coupled to outputs of said negative and positive threshold comparators, respectively; a one-shot delay circuit having an input coupled to an output of said OR gate; a latching flip-flop having a data input coupled to a positive output of said zero-crossing comparator and a clock input coupled to an output of said one-shot delay circuit.

Claim 10

A pulse detection circuit comprising: a differentiator coupled to receive an input signal, said input signal being a differential signal coupled across first and second input lines; a zero-crossing comparator coupled to an output of said differentiator; a negative threshold comparator having a first input coupled to a first one of said input lines and a second input coupled to a first threshold voltage; a positive threshold comparator having a first input coupled to a second one of said input lines and a second input coupled to a second threshold voltage; a first AND gate having a first input coupled to an output of said negative threshold comparator and a second input coupled to a positive output of said zero-crossing comparator; a second AND gate having a first input coupled to an output of said positive threshold comparator and a second input coupled to a negative output of said zero-crossing comparator; an OR gate having first and second inputs coupled to outputs of said negative and positive threshold comparators, respectively; a one-shot delay circuit having an input coupled to an output of said OR gate; a latching flip-flop having a data input coupled to a positive output of said zero-crossing comparator and a clock input coupled to an output of said one-shot delay circuit.

Claim 11

A pulse detection method comprising: detecting peaks in an input signal and producing a peak detect signal when a peak is detected; comparing said input signal to a threshold level; producing a qualified peak output signal when a peak is detected above said threshold level; and disabling said output signal for a predetermined period of time after a peak is detected.

Claim 12

A pulse detection method comprising: detecting peaks in an input signal and producing a peak detect signal when a peak is detected; comparing said input signal to a threshold level; producing a qualified peak output signal when a peak is detected above said threshold level; and disabling said output signal for a predetermined period of time after a peak is detected.

Claim 13

The method of claim 9 wherein said detecting step includes the steps of differentiating said input signal to produce a differentiated signal and detecting the zero-crossings of said differentiated signal.