Quad waveshaper for trapezoid quadrature thru zero VCO

Quad waveshaper for trapezoid quadrature VCO
Quad waveshaper for trapezoid quadrature VCO

This is the waveshaper for my Trapezoid quadrature through zero VCO. It gives the quadrature outputs for triangle, sine and the outputs for saw (ramp up, ramp down) and pulse. To use it you need my Trapezoid quadrature VCO. The waveshaper has no external input for waves, it is internally connected with the Trapezoid quadrature VCO

Specs and features

  • Four triangle quadrature outputs
  • Four sine quadrature outputs
  • Two saw (ramp up) outputs 90° apart
  • Two saw (ramp down) outputs 90° apart
  • Two pulse outputs 90° apart
  • Voltage controlled pulse width
  • Runs on +/-15V and +/-12V
  • Power consumption around 50mA each rail

The documentation and the Gerber files for download can be found in my website .

Schematic 01 quad waveshaper for quadrature thru zero VCO
Schematic 01 quad waveshaper for quadrature thru zero VCO
PCB quad waveshaper for quadrature thru zero VCO
Schematic 02 quad waveshaper for quadrature thru zero VCO

The triangle waves are created by algebraically averaging two trapezoid waves 90° apart. This is done here with IC3A for 270° and 0°. IC3C adds and averages 90° and 0°. You can use other combinations as well. IC3B and IC3D gives the inverse triangle waves. The sines are derived from the triangle with well known “old style” circuitry. The ramp outputs are build from two triangles 180° apart, level shifted and switched between them with the square wave. IC5A takes the 90° triangle, shift it up to 0..10V and lowers the amplitude to 0..5V. IC5B takes the 270° triangle shift it down to 0..-10V and lowers the amplitude to 0..-5V. IC6 (DG409) switches between this two triangles with means of the 270° square. Switching in the right moment put the needed parts of the triangle back together to the saw. The pulse outputs are done with the usual technique moving the switching point of a comparator around with the ramp wave.

PCB quad waveshaper for quadrature thru zero VCO
Triangle screenshot from quad waveshaper for quadrature thru zero VCO
Triangle screenshot from quad waveshaper for quadrature thru zero VCO
Sine screenshot from quad waveshaper for auadrature thru zero VCO
Sine screenshot from quad waveshaper for auadrature thru zero VCO
Saw screenshot from quad waveshaper for auadrature thru zero VCO
Saw screenshot from quad waveshaper for auadrature thru zero VCO
Pulse screenshot from quad waveshaper for auadrature thru zero VCO
Pulse screenshot from quad waveshaper for auadrature thru zero VCO
Quad waveshaper for auadrature thru zero VCO back view
Quad waveshaper for auadrature thru zero VCO back view