Yesterday, Benson Leung—Google engineer and intrepid USB-C cable tester—dropped the information on Twitter {that a} new USB-C cable specification has been released. The brand new spec permits for significantly heftier charging charges between compliant USB-PD units.
Comparatively minimal modifications
Though Leung factors out that the brand new specification has been beneath growth for 2 years, little or no has modified. Evaluating the USB-C 2.0 customary to right now’s 2.1 customary, the non-obligatory new Prolonged Energy Vary (EPR) specification—which bumps most voltage as much as 48 V, adequate to ship 240 W at 5 A—appears to be by far the biggest change.
From a client’s perspective, the bodily customary hasn’t modified—USB-C sort 2.1 units will plug into USB-C sort 2.0 ports, and vice versa. Underneath the hood, the requirements on the midplate have gotten stricter—a brand new paragraph has been added mandating that pins A4-A9 and B4-B9 (energy, energy supply, and legacy USB 2.0 help) should not quick to floor throughout connector mating.
In all probability the biggest quantity of added materials within the new specification regards the mathematics and engineering issues for predicting, detecting, and mitigating arcing when unplugging USB-PD cables. (Arcing whereas plugging them in shouldn’t be an issue, since excessive voltages aren’t initiated till after the cable is linked.) This is not a brand new downside—arcing can turn into an issue at solely 12 V—however the scope for potential harm will increase with the brand new larger voltage potential.
As well as, 5A Normal Energy Vary (SPR) cables are being deprecated completely, to get replaced by the brand new EPR cables. All full-featured cables (and cables rated for greater than 3 A present) are required to be electronically marked, permitting units to probe the cable itself for its energy supply capabilities (or lack thereof).
USB-PD EPR, laptops, and also you
The most important change by far within the new spec is help for USB Energy Supply at as much as 48 V and 5 A—multiply the 2 and also you get 240 W DC. Previous to the ratification of the brand new EPR customary, USB-PD was restricted to 100 W (20 V at 5 A).
The bump in energy supply will make it potential for producers to standardize USB-C chargers throughout their whole laptop computer product vary—even huge engineering laptops like those at the moment serviced by this Dell 240 W DC barrel jack charger. Sadly, this most likely will not make the chargers themselves common—there’ll doubtless proceed to be sufficient price distinction between ESR and EPR chargers that high-powered laptops will run in lowered efficiency mode on smaller chargers, simply as they do now.
The change ought to nonetheless result in a major lower in charger problem, although—as a result of although we’ll nonetheless have USB-PD SPR and USB-PD EPR chargers, that ought to just about be the extent of it. In the meantime, DC barrel jacks are available in a very staggering quantity of mechanical specs, with no less than 15 of these in common-enough utilization to be included in most “universal” laptop computer chargers.
