) chose to use BNC connections or 3W3/13W3 connectors (a sub-D with coaxial inserts) for a reason for their analog monitor connections.
#Common problems of usb b connectors professional
Some professional computer systems (SGI or IBM workstations. Granted, VGA uses a sub-D connector for (analog) high speed signals that can be in VHF range - and problems (signal degradation, ghosting.) are not that uncommon, even though there has been ample time for manufacturers to optimize HD15 connectors (which are probably mainly VGA use today) for their most common usage. Using it for a 400Mbps signal with a requirement of 500ps risetime could be considered ludicrous - if you ever toyed with experimental setups dealing with digital signals with even sub-10ns risetimes you will find that every inch of undisciplined wire or connector pin (as in, it is not part of a coax, or near a groundplane, or part of a twisted pair line) has a good chance of introducing gremlins into your system - or turning something innocent into an antenna. Certain EXACT models of Sub-D parts might be viable (as in, you have the part number and data sheet and have measured and tested that exact part).Ī DIN or Sub-D connector will be electrically suboptimal already for a 12Mbps signal (though they have been used for protocols in that speed range, eg AUI for ethernet transceivers). Generic Sub-D or DIN connectors are NOT designed to be viable VHF/UHF connectors.
High speed digital signals are effectively HF to UHF signals, with all the problems they bring. There might or might not have been foresight regarding USB2.0 and its signal integrity requirements. If the world is going to use connectors in their zillions then cost of tooling up is a non issue and IN-compatability with existing connectors is a bonus. With micro-USb the design means that the plug connector is the weaker point.
After many insertions the mini-USB in-device socket tends to fail. Micro USB was driven in large part by a then significant manufacturer's "need" for a lower profile socket BUT had the great advantage of making the cable the weaker link.
Mini USB was an interim step, with a major failing that the sockets and not the cables were the weak points. Relatively the original USB connectors were mechanically works of genius.ĭb9 is not too bad mechanically, but physically is far too large, and was already the host to substantial interconnect confusion. In practice Mini-DIN, when used frequently and by people not committed to keeping the connector intact, is an abomination and a disaster. Why did they not use mini-DIN or DE-9 or some other common connector of the time, instead of inventing entirely new physical connectors, which would then need to be manufactured with entirely new (expensive) machinery? At the time when the USB standard was being developed, there were a number of widely-available connectors that they could have used instead of making a new custom connector.