Precision triangle waveform generator

Claim 1

A precision triangle waveform generator for providing a triangular output signal of predetermined frequency having precise valued peaks, comprising: a first transistor having a first current electrode coupled to a terminal for receiving a positive supply voltage, a control electrode, and a second current electrode; first switching means for alternately connecting the second current electrode of the first transistor between a first reference voltage and an input node; a second transistor having a first current electrode connected to a terminal for receiving a negative supply voltage, a control electrode, and a second current electrode; second switching means for alternately connecting the second current electrode of the second transistor to the first reference voltage and to the input node; control means coupled to the control electrodes of the first and second transistors for controlling the first and second transistors in response to both a second reference voltage and the output signal; and integrating amplifier means having an input connected to the input node, and an output for providing the triangular output signal having positive and negative peaks proportional to the reference voltage.

Claim 7

A method for providing a triangular waveform having a precise positive peak value and a precise negative peak value, comprising the steps of: selectively charging a first capacitor to a first reference voltage; selectively charging a second capacitor to the negative peak value of the triangular waveform; integrating a charge difference between said first and second capacitors to provide a first control voltage; selectively charging a third capacitor to a second reference voltage; selectively charging a fourth capacitor to the positive peak value of the triangular waveform; integrating a charge difference between said third and fourth capacitors to provide a second control voltage; coupling said first control voltage to a first voltage controlled current source; coupling said second control voltage to a second voltage controlled current source; and alternately coupling said first and second current sources to an integrating amplifier for providing the triangular waveform, wherein said first and second current sources compensate said output waveform in response to the positive and negative peak values differing from a predetermined proportion of said first and second reference voltages, respectively.

Claim 8

A method for providing a triangular waveform having a precise positive peak value and a precise negative peak value, comprising the steps of: selectively charging a first capacitor to a first reference voltage; selectively charging a second capacitor to the negative peak value of the triangular waveform; integrating a charge difference between said first and second capacitors to provide a first control voltage; selectively charging a third capacitor to a second reference voltage; selectively charging a fourth capacitor to the positive peak value of the triangular waveform; integrating a charge difference between said third and fourth capacitors to provide a second control voltage; coupling said first control voltage to a first voltage controlled current source; coupling said second control voltage to a second voltage controlled current source; and alternately coupling said first and second current sources to an integrating amplifier for providing the triangular waveform, wherein said first and second current sources compensate said output waveform in response to the positive and negative peak values differing from a predetermined proportion of said first and second reference voltages, respectively.

Claim 9

A method for providing a triangular waveform having a precise positive peak value and a precise negative peak value, comprising the steps of: selectively charging a first capacitor to a reference voltage; selectively charging a second capacitor to a peak value of the triangular waveform; integrating a charge difference between said first and second capacitors to provide a control voltage; coupling said control voltage to a voltage controlled current source; and alternately coupling the voltage controlled current source and a second current source to an integrating amplifier for providing the triangular waveform, wherein said first and second current sources compensate said output waveform in response to the peak values differing from a predetermined proportion of said reference voltage.

Claim 10

A method for providing a triangular waveform having a precise positive peak value and a precise negative peak value, comprising the steps of: selectively charging a first capacitor to a reference voltage; selectively charging a second capacitor to a peak value of the triangular waveform; integrating a charge difference between said first and second capacitors to provide a control voltage; coupling said control voltage to a voltage controlled current source; and alternately coupling the voltage controlled current source and a second current source to an integrating amplifier for providing the triangular waveform, wherein said first and second current sources compensate said output waveform in response to the peak values differing from a predetermined proportion of said reference voltage.