Berg connector

Lore & Background

Berg connectors are manufactured by Berg Electronics Corporation of St. Louis, Missouri, now part of Amphenol. They usually have a pitch of 2.54 mm, with pins 0.64 mm square, and come as single or double row connectors. Many types exist, including the four-pin polarized Berg connectors used to connect 3½-inch floppy disk drive units to the power supply unit, often called a 'floppy power connector' or LP4; this connector has a 2.50 mm pitch, not 2.54 mm. Other types include two-pin Berg connectors used for front panel lights, turbo switch, and reset button, as well as two-pin Berg connectors used as jumpers for motherboard configuration.

The power connector on the 3½-inch floppy drive is informally known as 'the Berg connector'. The power cable from the ATX power supply consists of 20 AWG wire to a 4-pin female connector. The plastic connector housing is most often white (TE Connectivity / AMP 171822-4), but black is also common; other colours are rarer. The male PCB connector on the 3½-inch floppy drive is normally a polarized right-angle male header (TE Connectivity / AMP 171826-4), with a straight model (AMP 171825-4). The shape of the connector housing makes it very easy to determine pin number allocations by visual inspection.

In 1998, Berg Electronics was acquired by FCI (Framatome Connectors International) for $1.85 billion. In 2016, FCI Asia Pte was acquired by Amphenol.

Reader's Guide

The Berg connector's significance lies in its widespread use in IBM PC compatible hardware, particularly for powering 3½-inch floppy disk drives. As the standard floppy power connector (LP4), it became a familiar component in personal computers during the 1990s and early 2000s. Its 2.50 mm pitch distinguishes it from the more common 2.54 mm pitch of other Berg connectors. The connector's polarized design and color-coded housings (typically white or black) made it easy to identify and connect correctly. Beyond floppy drives, Berg connectors served as jumpers for motherboard configuration and as connectors for front panel controls, demonstrating their versatility in computer hardware. The acquisition of Berg Electronics by FCI in 1998 and later by Amphenol in 2016 reflects the consolidation of the connector industry. While the floppy drive connector has become less common with the decline of floppy disk drives, the Berg connector family remains a notable example of standardized computer interconnects, with its design influencing later connector types. The connector's legacy is tied to the era of 3½-inch floppy drives, where it provided a reliable, polarized power connection that was easy to visually inspect and assemble.

Did You Know?

• The Berg connector for floppy drives has a 2.50 mm pitch, not the typical 2.54 mm.
• The floppy power connector is often referred to as LP4.
• The plastic housing of the floppy power connector is most often white, but black is also common.