Nanofarad

A nanofarad (nF) is the SI unit of electrical capacitance equal to one billionth of a farad (1 nF = 10^-9 F). The name combines the prefix nano-, meaning one billionth, with the farad, the SI unit named after Michael Faraday. The nanofarad is a convenient unit for expressing small capacitances commonly used in electronic circuits.

In practical terms, 1 nF equals 1000 picofarads (pF) and 0.001 microfarads (µF). This makes the nanofarad a useful reference in designs where capacitor values fall between the larger microfarad and smaller picofarad ranges.

Applications of nanofarads appear across many electronics tasks. They are common in decoupling and filtering networks, signal coupling, and timing circuits. On printed circuit boards, 0.1 µF (100 nF) capacitors are widely used for noise suppression and stabilizing supply rails, often in combination with smaller values such as a few nF for higher-frequency paths.

When selecting capacitors, the nominal value is specified in nanofarads, together with a voltage rating and tolerance. Typical tolerances for ceramic capacitors are ±5% or ±10%. These values are printed on the component or documented in a bill of materials. The nanofarad thus serves as a practical unit for communicating small capacitances in a wide range of electronic designs.