Fan Terminations

This is a subsidiary page to the Fan Selection & Application Guide, which elaborates on the different values for the Termination attribute used to characterize AC and DC fans at Digi-Key.

At minimum, the electrical interface to a fan requires 2 conductors, one for current supply and another for return. Among regularly-stocked fans at Digi-Key this is the most common single configuration (particularly among AC-input devices) though the total number of all devices having 3 or more conductors is greater. These additional conductors are associated with a fan’s feedback and control features and can be used in a variety of different ways, which are discussed at greater length in the electrical interfacing section. Various interconnect styles used in fans sold by Digi-Key are described below.

The charts below show the relative prevalence of different termination styles among regularly-stocked products at Digi-Key at the time of writing, with termination styles found on 5 or fewer regularly-stocked products omitted for clarity.

Cord and Plug

A cord and plug termination style refers to a fan whose input leads are terminated to a common barrel-style power receptacle, co-packaged with a wall-mount AC adapter having a mating plug. It is not a common termination style among standard products at Digi-Key. P/N OD9225-SPOT pictured above is an example of such.

LP4 Assembly

An LP4 termination refers to an interconnect style commonly used in desktop computers. It is not a common termination style among standard products at Digi-Key. Part number 3159/ME80251V3-000U-G99 shown above is an example.

Rectangular Connector

Fans with a “rectangular connector” termination style are equipped with a rectangular-style connector, usually qualified with the number of connector positions present. It does not imply any specific style or type of such connector. Part numbers TF037F-2000-F and BFB0312HA-A116 above are two examples.

This also is a relatively uncommon termination style among regularly-stocked products, because of the greater flexibility afforded by not applying a connector to unterminated fan leads until such time as the desired connector and pinout have been identified. Note that Digi-Key offers limited custom assembly capabilities, and is capable of assembling a variety of connector types to fans having wire leads, to a customer’s specification. Setup fees, per-unit charges, and minimum orders do apply; for more information contact

Terminal Block

Terminal blocks are a type of connector which facilitates connection to discrete, free-hanging conductors or (in some instances) to a mating portion of a terminal block system which does so. While not particularly common, it is more frequently encountered in context of AC-input fans than among DC-powered devices. Part number W2E200-HH86-01 above is an example.


In context of fans, a “terminal” style interface usually implies use of a standard size quick-disconnect system, often implemented in such a manner as to allow use of either discrete wires with suitable terminals applied, or a purpose-specific cord which integrates suitable connectors on an appropriate mounting pitch in an overmolded cable assembly. This is a relatively common termination style particularly among AC fans, with the 2-terminal style being most frequently encountered. Part number UF12A12-BTHR above is an example.


Fans with a USB termination are equipped with a common USB Type-A connector, which allows sourcing power from typical USB host sources. It is not commonly encountered in Digi-Key’s product portfolio, with the obsolete P/N 9120-20 being the sole example at the time of writing.

Wire Leads

The use of discrete, non-terminated lead wires is the most frequently-encountered termination style among regularly stocked fan products at Digi-Key at the time of writing. Products may ship with a variety of wire preparations depending on the product, including being stripped, partially stripped, stripped and tinned (most common) or simply cut to length. Part number HA80251V4-000U-999 above is an example.