What Is a Pitch to Voltage Converter?

A pitch to voltage converter is a kind of device that allows the determination of an audio waveform’s frequencies and creates control voltage. This is then applied to a calibrated oscillator’s control input, which makes the oscillator output an audio signal of its own at the exact frequency as the initial audio waveform. Oftentimes, the pitch to voltage converter has a responsive switching circuit which allows it to respond to input signals crossing at zero in a positive direction for capacitor charging to a negative voltage peak. Upon discharge of the capacitor through a certain resistor to a voltage that is positive, the capacitor will recharge once an input signal crosses zero again to a positive direction. This charge that is at peak voltage is coupled onto a particular holding circuit, providing a direct current (DC) voltage that is proportional to the initial input signal’s frequency.

Some variations of the pitch to voltage converter may include operational amplifiers for processing of simple linear signals. They may also include a network of tiny resistor-capacitors (RCs) for the removal of frequency ripples. These types of converters are able to receive both DC voltages and alternate current (AC), and they may receive signals from devices including tachometers, encoders, timers, etc.

The pitch to voltage converter can be an analog model, with circuitry that allows for demodulation of frequency modulated signals that the converter emits and receives. This converter includes a means of input signal supplying that has a varied rate of repetition within a determined range while having means to supply reference signals that repeat at a fixed rate. The means for responsiveness includes development of a framing signal that has a rate of repetition which is higher than that of other signals. Another means of responsiveness includes a framing signal with a rate of repetition less than another signal’s rate of repetition. What eventually occurs is that other signals mix with each other, developing new signals with new rates of repetition distinguished from the initial framing signals that were inputted to the pitch to voltage converter.

Different fields use the pitch to voltage converter for an array of purposes and functions. Some models are used for integrated circuits or simply to bolt to walls in building construction. In testing vehicles, the pitch to voltage converter is used to evaluate response times that include air-conditioning, clutches, or brake systems. They may also be used in engine motors to control the speed of an engine.