WAVEFORM DISCRIMINATING CIRCUIT

• US 3,676,783 A
• Filed: 03/25/1969
• Issued: 07/11/1972
• Est. Priority Date: 04/23/1968
• Status: Expired due to Term

• Current Assignee: Setsuro Kinbara, Tadashi Kumahara
• Original Assignee: Setsuro Kinbara, Tadashi Kumahara
• Inventors: Kinbara, Setsuro, Kumahara, Tadashi
• Primary Examiner(s): Forrer, Donald D.
• Assistant Examiner(s): Carter, David M.
• Application Number:
  US04/810,223
• Time in Patent Office: 1,204 Days
• Field of Search: 307/235 328/115,116,117,112,147
• US Class Current: 327/70
• CPC Class Codes: G01T 1/38 Particle discrimination and measurement of relative mass, e.g. by measurement of loss of energy with distance (dE/dx) constructional details of semiconductor detectors therefor H01L31/00
• CPC Class Codes: H03K 5/153 Arrangements in which a pulse is delivered at the instant when a predetermined characteristic of an input signal is present or at a fixed time interval after this instant switching at zero crossing H03K17/13

Abstract

A pulse shape discriminating circuit comprising an input terminal for receiving an input signal, a plurality of characteristic circuits having their inputs connected in common to said input terminal, first and second amplitude discriminating circuits each receiving shaped pulses from the characteristic circuits associated therewith, and a mixing circuit for combining the pulses from said first and second amplitude discriminating circuits. The first amplitude discriminating circuit generates a first step pulse representative of the time which corresponds to a first point on said input signal, said first point having a value equal to a first preselected percentage of the peak value of said input signal, the second amplitude discriminating circuit generates a second step pulse representative of the time which corresponds to a second point on said input signal, said second point having a value equal to a second preselected percentage of the peak value of said input signal, and the mixing circuit generates a rectangular pulse waveform having width equal to the time interval between said first and second points.

Claims

1. A pulse-shape discriminating circuit comprising an input terminal for receiving an input signal, first and second signal channel means having their input ends connected in common to said input terminal, said first signal channel means producing a first shaped pulse representative of a time interval corresponding to a first point on said input signal, said first point having an amplitude which is a first predetermined percentage of the peak value of said input signal, the first signal channel means comprising first and second characteristic circuits having their input ends connected in common to said input terminal and producing at their output ends signals each having a magnitude proportional to the magnitude of said input signal, first and second dividing resistors each connected in series to said first and second characteristic circuits, and a first amplitude discriminating circuit having input ends connected respectively to taps on said first and second resistors, said first and second characteristic circuits having different electrical characteristics, said second signal channel means producing a second shaped pulse representative of a time interval corresponding to a second point on said input signal, said second point having an amplitude which is a second predetermined percentage of the peak value of said input signal, the second signal channel means comprises third and fourth characteristic circuits having their input ends connected in common to said input terminal and producing at their output ends signals each having a magnitude proportional to the magnitude of said input signal, third and fourth dividing resistors each connected in series to said third and fourth characteristic circuits, and a second amplitude discriminating circuit having input ends connected respectively to taps on said third and fourth resistors, said third and fourth characteristic circuits having different electrical characteristics, each of said characteristic circuits being defined as a circuit having an electrical characteristic selected from a delaying, an attenuating, a differentiating, an integrating, and a stretching effect or appropriate combination thereof;

and means for combining said first and second shaped pulses to produce an output pulse representative of the time interval between said first and second points.

2. A pulse-shape discriminating circuit comprising an input terminal for receiving an input signal, first and second signal channel means having their input ends connected in common to said input terminal, said first signal channel means producing a first shaped pulse representative of a time interval corresponding to a first point on said input signal, said first point having an amplitude which is a first predetermined percentage of the peak value of said input signal, and the first signal channel means including a first characteristic circuit, said second signal channel means producing a second shaped pulse representative of a time interval corresponding to a second point on said input signal, said second point having an amplitude which is a second predetermined percentage of the peak value of said input signal, and the second signal channel means including a second characteristic circuit, the first and second signal channel means including a third characteristic circuit in common to both of them;

and the pulse-shape discriminating circuit further including inverter means connected in series to said third characteristic circuit, two pairs of dividing circuits each consisting of two resistors and having first and second intermediate junctions therebetween respectively, one end of each of said dividing circuits being connected in common tO a junction to which said inverter means is connected, the other ends of said divider circuits being connected respectively to said first and second characteristic circuits, first and second amplitude limiting circuits connected respectively to said first and second junctions, and first and second amplitude discriminating circuits each having one input end connected respectively to said first and second junctions and the other input end connected respectively to a reference level; and

means for combining said first and second shaped pulses to produce an output pulse representative of the time interval between said first and second points.

3. A pulse-shape discriminating circuit as set forth in claim 1 wherein the first characteristic circuit has an attenuating characteristic, the second characteristic circuit has a delaying characteristic, the third characteristic circuit has an attenuating characteristic different from that of said first characteristic circuit, and the fourth characteristic circuit has a delaying characteristic similar to that of said second characteristic circuit, and wherein the means for combining the first and second shaped pulses comprises of a mixer providing a rectangular pulse waveforms having width representative of the rise-time of the input pulse.

4. A pulse-shape discriminating circuit as set forth in claim 2 wherein a width-to-pulse height converter is connected to said means for combining the first and second shaped pulses, whereby an output pulse having a height proportional to the rise-time of said input signal is produced at the output terminal of the converter.