Ben's Website

Serious musings

Standardizing the Future

Apple's resistance to standardized cellphone charging is disappointing and discouraging: Apple doesn't want to be prevented from engineering its own, ever smaller connectors for ever rounder rectangles. Ignoring the great progress in wireless charging, the better question is: why is Apple lobbying when it could be improving its devices?

One of the oddly unsolved problems in cellphones is their daily ability to overcharge their batteries. While other high-demand battery devices - cordless power tools - have solved this by making the chargers more intelligent and thus able to stop charging when the battery is 'full.'

Apple could take this standardization conversation in a useful direction by proposing chargers that advertise their ability to supply power on connection. As any Kill-a-Watt will tell, most chargers and other power supplies waste energy when not powering a device. If the chargers were made more intelligent, they would be able control how much power they supply to a connected device. A cellphone could then request the charger's full capability during a fast-charge, switch to a trickle for standby functions, and stop supplying power entirely when the device is disconnected.

This improved charger requires two things: power control and some method of communication to attached devices. Power control entails a switch on a transformer's high-side to gate power, or in a switched mode supply, the switching duty cycle needs to be variable (across the entire range, or more likely 100%, 5%, 0%). Ultra low power microcontrollers can be powered off the wall plug, parasitically. And since we're unlikely to move back to barrel or other non-USB charging interfaces, communication is quite easy.

So, why Apple? Apple is one of the few companies that takes pains to control the entirety of their product. They enjoy broad customer support, have healthy profit margins, and frequently claim a beneficent attitude towards their customer and the environment. As such, they have the engineering, market, and cultural position to make this smart-charging technology cool, to paint it as an obviously good thing for all involved. That they can't see this opportunity is unfortunate.