At EasyTechJunkie, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What is a Frequency to Voltage Converter?

Mal Baxter
Mal Baxter

A frequency to voltage converter is a piece of technical equipment that translates currents, frequencies, pulses, and other waveforms into proportional electrical output. The voltage output corresponds to the fluctuations of the input signal. They can modulate frequencies to limit output, usually expressed in volts (v), volts direct, or alternating current. This equipment is often employed in electromechanical contexts, as in evaluation of the responsiveness of vehicle engine or safety components.

Frequency to voltage converter technology contains various filters or resistor-capacitors for managing signals and reducing extraneous bands. An operational amplifier processes linear signals. These converters are used in numerous industries and processes. They evaluate automobile tachometers and speedometers. Converters monitor response times of vehicle controls, switches and safety systems. Information is read from encoders, timers and relays, while devices output voltage modulated within programmable parameters.

Woman posing
Woman posing

The available form factors for frequency to voltage converter equipment are designed for integration within a wide range of systems. Some can be bolted to walls or mounted in racks. Modular components stack while bench units offer full casings. Others mount to computer circuits, or fasten within enclosures and computer backplanes.

In addition to evaluating engine speeds and component response times, they can monitor flowmeter data. Other units assist in machine analysis and control. Converters also assist vehicle drivers and pilots to select appropriate gear and throttle configuration safely within an engine's rotation rate.

Numerous capabilities are afforded by this convertibility between frequency and electronics; making this technology not only common, but a vital component to modern industry. Some warn drivers when they are speeding, and also manage clutching, horn and door lock mechanisms. Others sense the speed of trains and estimate traffic volumes. They adjust the speed of analog audio recorders, and they time engine hours. Frequency to voltage converter equipment services not only analog, but also digital technology.

Specifications of a frequency to voltage converter can include analog or differential channels. A differential channel simply bridges two different systems by regulating voltage between the two inputs, outputting an appropriate signal response. Other factors can consist of processes that manage the maximum output in voltage; optical, magnetic induction, or capacitance for signal isolation; and accuracy tolerances.

Expanding technical markets, and growing need for energy saving processes create continued demand for this technology. It assists in analysis, problem solving, and creating automated systems for industrial and consumer products. Use of this technology enhances safety systems and increases efficiency across multiple technologies and industries.

Discussion Comments


@hamje32 - If the output of this device is alternating current (AC) then it would make sense that it would be used in an AC converter or a DC voltage converter that generates AC current as the output.

You might also see it in a power transformer, which is also known as step up or step down transformer. I have a couple of these from my overseas travels where their AC outlets used 220 volts instead of 110 like we have in the United States.


@Charred - I worked in the electrical utility industry for quite some time. While I was not an engineer myself I worked around other relay technicians.

They were doing all sorts of weird stuff with relays and meters and waveform equipment. I would bet anything that this type of technology is used by relay technicians, to measure the response times of relay equipment.

They read those pulses directly from the relay equipment and it appears as waveforms on the meters. Like I said I don’t know what all the stuff means but it makes sense that the testing equipment would use these kinds of circuits. It’s possible they also use a voltage to frequency converter too, since they want to measure fault tolerances for high and low currents.


@David09 - The article mentions alternating current, which I believe oscillates. So I think there is some correlation between alternating current and the input frequency which also oscillates as you point out.

How it works I’m not sure, but I agree, I don’t view this as a mechanism for building some big power transformer. I like how it’s used in automobiles to warn drivers when they’re speeding.

My take is that it “reads” the speedometer frequency and uses that to generate voltage for the warning signal. That would be very handy, especially to someone like me! Perhaps they will one day expand the technology so that it can read the waveforms in your brain; it will then instantly know when you’re drowsy and about to fall asleep at the wheel.


I’d think there would have to be limitations on the power output of the voltage since you’re using frequency signals as your inputs and not direct electrical currents.

I’m guessing it would be enough voltage to appear as an oscillation on a waveform monitor but probably not more powerful than that. I’m not an electrician of course; that’s just my guess based on the applications that are mentioned in the article.

I’ve seen a frequency to voltage converter circuit and it seems to be somewhat simple in its design, so I wouldn’t expect to it to generate tons of voltage in the output in my opinion.

Post your comments
Forgot password?
    • Woman posing
      Woman posing