Usage
The 25-pin D-sub connector is occasionally used in recording studios for multi-channel analog audio and AES digital audio.
The D-sub connector family is now in decline for general usage in the computer industry, due to size and cost. For portable devices such as PDAs, MP3 players or mobile phones, the D-sub connector is usually too large to fit. In the laptop computer sector, where weight and size are crucial, many models no longer include D-subs. Even small form factor desktop PCs may find D-sub connectors too large for their value.
Because of its relative complexity (the D-shaped metal shield, the screws and nuts), D-sub connectors are now quite expensive compared to other, mostly simpler, common connectors. In the retail PC world where margins are very thin, these connectors are a natural target for removal.
The physical design of D-sub connectors is ill-suited for consumer plug-and-play applications. Thin metal pins, especially in higher-density connectors, are easily bent or broken, particularly if frequently plugged in by touch behind equipment. The need to tighten screws for a secure connection is cumbersome. Although ESD- and EMI-resistant D-sub connectors exist, the fundamental design was never intended to protect from electrostatic discharge or electromagnetic interference or facilitate very high frequency interconnections.
For video purposes, the DE15HD connector is in the process of being replaced by DVI and HDMI connectors. A notable exception to this replacement is on the many analog CRT monitors still in use: the analog version of the DVI connector is similar in price and more complex than the D-sub, so the shift away from D-subs is slow in this case. For the majority of other consumer applications, D-sub serial and parallel connectors have been replaced by the physically much simpler and cheaper IEEE 1394 (FireWire), SATA, USB, or modular connectors. All of these connectors are much less rugged and durable than D-sub connectors—for example, the SATA connector as part of a cable assembly is specified to withstand only 50 manual insertions—but the robustness of the D-sub is more than is needed in many consumer product applications.
Due to the environments within factories and mills, serial and parallel protocols are commonly used (and in some cases current standards) for their combination of maximum cable length, sufficient speed, and compatibility with old equipment with long life expectancies. As D-Sub connectors have remained popular with these specifications, D-Subs are still commonly in use today where their robustness is required. The connectors' pricing is also less of a concern as most industrial equipment is limited in production with higher mark up per unit and is generally expected to be supported by service contracts.
Read more about this topic: D-subminiature
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