Molex Inc. is listed on the Nasdaq National Market under MOLX manufacturer of electronic components, including electrical and fiber optic connectors, switches, integrated products and special tools.

The company was founded in 1938 and is now active worldwide with a turnover of over 2 billion U.S. $ and over 100,000 products.

Molex is an original equipment in industries such as automotive, consumer, industrial and office equipment, building cabling and telecommunications.

Most manufactured by Molex connector carry the little shortcut ( Acronym ) MXI for Molex Inc.

Molex connector


Molex manufactures different, sometimes highly complex, high-quality and customer- specific or system-specific connectors, capacitors, and connectors of very simple construction such as those used in the power supply to the PC.


In the language Molex is partly become the generic name, ie it is often referred to as a Molex connector plug such type, without having to necessarily actually be products from Molex, the manufacturer.

Molex connectors in industrial electronics

In plants and in the automotive industry quality, robust and often application-specific or application- matched connectors are usually used. Here also design details such as impurity strength, IP protection, and mechanical Abziehschutz Ansteck-/Abziehhilfen (eg lever ) play a major role.

Molex connectors in PCs

In conventional PCs comparatively very simple, standardized plug shapes are used, which are executed by some manufacturers also inferior with cheap materials, service life, strength and material thicknesses.

Power cable

Connector for power supply in computers are referred to in common parlance as a " molex " even if Molex is not the only manufacturer.

The larger 4 -pin connector (Molex 8981 series ) is used for power supply of hard drives, CD - ROM drives and other internal devices with medium to high energy intake (but also for some fans, mostly a rather low energy consumption have ). Originally it was " used floppy drives. The smaller 4- pin type is mainly for 3.5" for 5.25 thought floppy drives. Currently units are usually powered via SATA or USB ports with power. However, the floppy Connector sometimes for other devices such as fans " misused ".

The colors are not chosen arbitrarily. The red ladder leads 5 V, 12 V, the yellow and the two black wires are grounded. The Molex connector above contain no metal pins in the proper sense, but small bushes. The pins are located on the drives or on the motherboard itself

Connector to PC fans

With the name you Molex also combines a smaller, three-pin female connector that is on the corresponding counterpart (usually on the motherboard ) connected. Be connected with it, especially fans. The pins cause mass ( black), 12 V ( red ) and if the tacho signal ( from the revolution sensor ) of the fan ( yellow or blue).

Since about 2005, there are also four-pin connectors of this kind Here comes the pulse-width modulation (PWM) signal to the fan added a blue line. The PWM signal controls the speed of the fan.

Four-pin plugs can be stuck on three pin connectors. The asymmetric shape connector with two guide rails on one side ensures that even in this case the correct cables are connected (which, however, assumes that the corresponding guide plate of the male terminal is available). The blue PWM line remains free in this case, the ability of the fan motor with the pulse width modulation is not used. Just like a three-pin PWM connector can be performed in this case by a suitably equipped motherboard, so that the fan speed to be controlled anyway.

In quiet fans, it is sufficient possibly to completely give up control. In this case, can be powered directly from the 12V power supply of a large Molexsteckers with the aid of an adapter cable a fan. The tachometer cable and possibly the PWM signal, remain unused ( nc ).


Frederick August Krehbiel founded 1938, the Molex Products Company in Brookfield, Illinois. He named the company after Molex, a plastic material, which he had developed. Shortly thereafter, a number of products made ​​therefrom, including watch cases, flower pots, round handle of rotary valves and salt tablet dispenser.

1940 occurred at a of Krehbiels sons, John H. Krehbiel Sr., the company and discovered early the excellent electrical insulation properties of the material. A few years later, the company introduced the metal stamping into their Abformungsprozesse, from which the first plug-in for Appliances from General Electric and other manufacturers emerged.

In the fifties, Molex penetrated with its low-cost connector blocks quickly advance in the equipment market. The company introduced in 1953 for the first time before a connection after the male-female principle. In the following years Molex expanded the range of products for commercial and residential applications.

1960, before the first Molex plug and socket connection from nylon, which meant that Molex now advanced to the electronics company.

In 1967 Molex to operate internationally. The first factory was opened in 1970 in Japan, the second in 1971 in Ireland. Today, more than two thirds of the annual revenue from products that are manufactured and sold outside the United States arise.

Molex kept pace in the eighties with the growth of the electronics industry by the product offering was extended to the needs of the computer industry and the operation of equipment. The company also established itself as a supplier to the automotive industry.

In the early nineties markets such as telecommunications, industrial automation and premise networking were developed.

Molex has strengthened its own position in key markets and is expanding through growth and several strategic acquisitions. 2006 acquired the company Molex Woodhead Industries, the largest acquisition in the company's history. This results in a stronger presence in the factory automation and other heavy industrial areas.

In September 2013, the US-based Koch Industries announced headquartered in Wichita, Kansas to the acquisition of Molex for around 7.2 billion U.S. dollars.

Molex in France

Molex has settled in France in 2004. They had there a development department in Montigny -le- Bretonneux ( Yvelines) and a factory in Villemur -sur -Tarn (Haute -Garonne), two sites that were sold by the SNECMA shortly before its merger with Sagem and by the year 2000 the companies RCA Connecteur and Labinal included. The factory of Villemur -sur -Tarn has existed since 1932., The part assumed by Molex had 283 persons ( 2008) and supplied mainly PSA Peugeot Citroën. Another part was ( incorporated since 2005 in the SAFRAN Group ) of Labinal keep. It produces connectors for the aerospace and employs approximately 600 people.

Since October 2008, the factory of Molex Villemur -sur -Tarn was threatened with closure. It was pulled a shift to China and the United States into account. The French co-CEO Marcus Kerriou and William Brosnan have their farewell filed on 6 August 2009, after being involved in a brawl with the striking employees, and left the management of the U.S. Department of Molex group. A ministerial arbitrator, Francis Latarche, former director of DDTE (Les Territorial Units, formerly Directions Departmental de l' emploi, du travail et de la formation professionnelle ( DDTEFP ) called ), was appointed by Christian Estrosi, the Minister of Industry. Then carried out in the course of 2010, the final closure despite the prolonged protests and actions of the workforce.