Editing Analog-to-digital converter (section)

=== Measuring physical values other than voltage ===
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Although the term ADC is usually associated with measurement of an analog voltage, some partially-electronic devices that convert some measurable physical analog quantity into a digital number can also be considered ADCs, for instance:

* [[Rotary encoder]]s convert from an analog physical quantity that mechanically produces an amount of [[Rotation around a fixed axis|rotation]] into a stream of digital [[Gray code]] that a [[microcontroller]] can digitally interpret to derive the direction of rotation, angular position, and rotational speed.<ref>{{Cite web |date=2019-10-01 |title=How to Use Rotary Encoders to Quickly Convert Mechanical Rotation into Digital Signals |url=https://www.techbriefs.com/component/content/article/tb/supplements/md/features/articles/35291 |access-date=2023-10-09 |website=Techbriefs}}</ref>
* [[Capacitive sensing]] converts from the analog physical quantity of a [[capacitance]]. That capacitance could be a [[Proxy (statistics)|proxy]] for some other physical quantity, such as the distance some metal object is from a metal sensing plate, or the amount of water in a tank, or the [[permittivity]] of a [[dielectric]] material.
** Capacitive-to-digital (CDC) converters determine capacitance by applying a known excitation to a plate of a [[capacitor]] and measuring its charge.<ref>{{Cite web |last=Jia |first=Ning |date=2012-05-01 |title=ADI Capacitance-to-Digital Converter Technology in Healthcare Applications |url=https://www.analog.com/en/analog-dialogue/articles/capacitance-to-digital-converter-technology-healthcare.html |url-status=live |archive-url=https://web.archive.org/web/20230707111410/https://www.analog.com/en/analog-dialogue/articles/capacitance-to-digital-converter-technology-healthcare.html |archive-date=2023-07-07 |access-date=2023-10-09 |website=[[Analog Dialogue]]}}</ref>
* [[Digital calipers]] convert from the analog physical quantity of an amount of displacement between two sliding rulers.
* Inductive-to-digital converters measure a change of [[inductance]] by a conductive target moving in an [[inductor]]'s [[Alternating current|AC]] [[magnetic field]].<ref>{{Cite web |last=Kasemsadeh |first=Ben |date=2015-07-31 |title=How To Sense Lateral Movement Using An Inductance-to-Digital Converter |url=https://www.fierceelectronics.com/components/how-to-sense-lateral-movement-using-inductance-to-digital-converter |url-status=live |archive-url=https://web.archive.org/web/20231009202429/https://www.fierceelectronics.com/components/how-to-sense-lateral-movement-using-inductance-to-digital-converter |archive-date=2023-10-09 |access-date=2023-10-09 |website=Fierce Electronics}}</ref>
* [[Time-to-digital converter|Time-to-digital converters]] recognize events and provide a digital representation of the analog [[time]] they occurred.
** [[Time of flight]] measurements for instance can convert from some analog quantity that affects a [[propagation delay]] for an event.
* [[Sensor]]s in general that don't directly produce a voltage may indirectly produce a voltage or through other ways be converted into a digital value.
** Resistive output (e.g. from a [[potentiometer]] or a [[force-sensing resistor]]) can be made into a voltage by sending a known current through it, or can be made into a [[RC time constant|RC charging time]] measurement, to produce a digital result.