{"id":25282,"date":"2016-08-11T10:58:51","date_gmt":"2016-08-11T10:58:51","guid":{"rendered":"http:\/\/randomnerdtutorials.com\/?p=25282"},"modified":"2019-07-16T14:46:08","modified_gmt":"2019-07-16T14:46:08","slug":"electronics-basics-how-a-potentiometer-works","status":"publish","type":"post","link":"https:\/\/randomnerdtutorials.com\/electronics-basics-how-a-potentiometer-works\/","title":{"rendered":"Electronics Basics – How a Potentiometer Works"},"content":{"rendered":"\n

A potentiometer also referred to as pot may come in a wide variety of shapes\u00a0and are used in many applications in your daily life, for example to control the audio volume of the radio.<\/p>\n\n\n\n

A pot is a manually adjustable variable resistor with three terminals. In the figure below you can see some examples of potentiometers.<\/p>\n\n\n\n

\"Electronics<\/figure><\/div>\n\n\n\n

Potentiometer Symbols<\/h2>\n\n\n\n

In a circuit diagram, a potentiometer<\/a> is represented by one of the two symbols below:<\/p>\n\n\n\n

\"Potentiometer<\/figure><\/div>\n\n\n\n

How Does a Potentiometer Work?<\/h2>\n\n\n\n

A potentiometer has 3 pins. Two terminals (the blue and green) are connected to a resistive element and the third terminal (the black one) is connected to an adjustable wiper.<\/p>\n\n\n\n

\"How<\/figure><\/div>\n\n\n\n

The potentiometer can work as a rheostat <\/strong>(variable resistor) or as a voltage divider<\/strong>.<\/p>\n\n\n\n

Rheostat<\/h2>\n\n\n\n

To use the potentiometer as a rheostat, only two pins are used: one outside pin and the center pin. The position of the wiper determines how much resistance the potentiometer is imposing to the circuit, as the figure demonstrates:<\/p>\n\n\n\n

\"Use<\/figure><\/div>\n\n\n\n

If we have a 10k\u03a9 potentiometer, it means that the maximum resistance of the variable resistor is 10k\u03a9 and the minimum is 0\u03a9. This means that by changing the wiper position, you get a value between 0\u03a9 and 10k\u03a9.<\/p>\n\n\n\n

Voltage Divider<\/h2>\n\n\n\n

Potentiometers can be used as voltage dividers. To use the potentiometer as a voltage divider, all the three pins are connected. One of the outer pins is connected to the GND, the other to Vcc and the middle pin is the voltage output.<\/p>\n\n\n\n

\"Potentiometer<\/figure><\/div>\n\n\n\n

When the potentiometer is used as a voltage divider, the wiper position determines the output voltage. When you have the potentiometer connected this way, you have the following circuit:<\/p>\n\n\n\n

\"Potentiometer<\/figure><\/div>\n\n\n\n

Basically, the voltage divider is used to turn a large voltage into a smaller one.<\/p>\n\n\n\n

The output voltage can be calculated using the following equation obtained from Ohm\u2019s Law:<\/p>\n\n\n\n

\"Formula<\/figure><\/div>\n\n\n\n

Potentiometer Taper<\/h2>\n\n\n\n

One main concept associated with potentiometers is the taper<\/strong>. The taper is the relationship between the position and the resistance of the potentiometer. The most common types are linear <\/strong>and logarithmic <\/strong>tapers.<\/p>\n\n\n\n

Linear potentiometers<\/h3>\n\n\n\n

The most common form is the simple linear taper. In a linear taper, the relationship between the resistance and the potentiometer position is linear.<\/p>\n\n\n\n

This means that if the knob of the potentiometer is at the medium position, the output voltage is half of the voltage through the potentiometer. See the figure below:<\/p>\n\n\n\n

\"Potentiometer<\/figure><\/div>\n\n\n\n

Potentiometers with linear taper are marked with a B.<\/p>\n\n\n\n

\"Potentiometer<\/figure><\/div>\n\n\n\n

Logarithmic potentiometers<\/h3>\n\n\n\n

Non-linear tapers are specially used in audio control applications, namely logarithmic tapers<\/strong> (there are also inverse-logarithmic<\/strong> tapers). The relationship between the position and the resistance is shown in the following figure:<\/p>\n\n\n\n

\"Potentiometer<\/figure><\/div>\n\n\n\n

Potentiometers with logarithmic taper are marked with an A.<\/p>\n\n\n\n

\"Potentiometer<\/figure><\/div>\n\n\n\n

Wrapping Up<\/h2>\n\n\n\n

I hope you’ve learn something new today and you’ve found this explanation useful.<\/p>\n\n\n\n

If you’d like to know more about electronics basics or if you’d like to start into the world of electronics make sure you check out our Electronics for Beginners eBook<\/strong><\/a>.<\/p>\n\n\n\n

Thanks for reading.<\/p>\n","protected":false},"excerpt":{"rendered":"

A potentiometer also referred to as pot may come in a wide variety of shapes\u00a0and are used in many applications in your daily life, for example to control the audio … <\/p>\n

CONTINUE READING \u00bb<\/a><\/p>\n","protected":false},"author":1,"featured_media":25326,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[305,3,256,269,264,8],"tags":[],"class_list":["post-25282","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-0-other","category-circuits","category-electronics","category-guide-project","category-project","category-c-theory-and-blog"],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/08\/Fig.-1.jpg?fit=700%2C393&quality=100&strip=all&ssl=1","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/posts\/25282","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/comments?post=25282"}],"version-history":[{"count":0,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/posts\/25282\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/media\/25326"}],"wp:attachment":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/media?parent=25282"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/categories?post=25282"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/tags?post=25282"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}