Don’t get me wrong — I do like standard connectors. A while back, I wrote about how the micro-USB connector became the standard power/data connector for mobile phones. Well, that is unless you own an iPhone.
The good news is that we do have a standard power connector for 12 VDC in automobiles. The bad news is that it is an ugly behemoth derived from — can you believe it? — a cigarette lighter. For some background and history, see the Wikipedia article. The Society of Automotive Engineers (SAE) has a standard that describes this power connector (SAE J563). Alan K0BG correctly warns us to “never, ever use existing vehicle wiring to power any amateur radio gear” including the 12 volt accessory plug. (I always follow this advice, except in the cases when I don’t.) I also found this piece by Bill W8LV on eham.net that describes the crappiness of these connectors.
Well, there is a new standard power connector showing up in cars: the USB port. These ports provide the data and power interface for mobile phones, integrating them into the auto’s audio system. Standard USB ports (USB 1.x or 2.0) have a 5V output that can deliver up to 0.5A, resulting in 2.5W of power. A USB Charging Port can source up to 1.5A at 5V, for 7.5 W of power. This is not that great for powering even low power (QRP) ham radio equipment.
Now a new standard, USB Power Delivery, is being developed that will source up to 100W of power. The plan is for the interface to negotiate a higher voltage output (up to 20V) with 5A of current. Wow, now that is some serious power. We will have to see if this standard is broadly adopted.
Two things are obvious to me: 1) the old cigarette lighter connector needs to go away and 2) it is not clear what the replacement will be.
What do you think? Any ideas for the next generation of 12V automotive connector?
73, Bob K0NR