Go Back   World-Designs-Forum > FAQ > FAQ - Technology
Register FAQ Members List Calendar Gallery Today's Posts Mark Forums Read

FAQ - Technology Audio Component Technology

Thread Tools Display Modes
Old 6th January 2006, 10:16 PM
FAQ Team FAQ Team is offline
FAQ *****istrator
Join Date: Jan 2006
Location: faq
Posts: 44
Default Written capacitance units

The Greek letter mu (like a u but with a tail starting the letter) is the correct symbol for micro which means millionth.

Mu isn't available on many keyboards so m is sometimes used instead. This can be confusing though as m is used in the SI system for milli, which is a thousandth, and there is a capacitance unit of a millifarad although it's not often used.

In older circuits you often see mmf which is not m for milli either but means million millionths of a farad, or pF picofarads as we know them now.

In electronics it is safer to use the keyboard letter u for the Greek letter mu as it looks similar and can`t be confused with any other notation.

The units are,

1 Farad (F) =

1000 milli Farad (mF - not generally used) =

1000 000 micro Farad (uF) =

1000 000 000 nano Farad (nF) =

1000 000 000 000 pico Farad (pF - old mmF)

Some capacitor values may be marked in alternative ways such as a number followed by K being used to show thousands of pF (= number of nF).

Most formulae use the full Farad, so convert the value for calculations. The units relate by thousands/thousandths so remembering their names, including milliFarads, is useful for this.


10,000pF = 10nF = .01uF = .00001mF = .00000001F

All we do is move the decimal point 3 places at a time. If doing a calculation (i.e. to find the impedance of the capacitor at a known frequency) the last value, expressed in Farads, would be the one to use

Last edited by John Caswell; 1st November 2013 at 04:47 PM.

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
AER drive units Max N Loudspeakers 1 28th September 2006 11:24 AM

All times are GMT +1. The time now is 05:53 PM.

Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
Copyright World Designs