Yesterday, Benson Leung—Google engineer and intrepid USB-C cable tester—dropped the news on Twitter that a new USB-C cable specification has been

New USB-C Type 2.1 standard offers up to 240 W power delivery

submited by
Style Pass
2021-05-26 12:00:12

Yesterday, Benson Leung—Google engineer and intrepid USB-C cable tester—dropped the news on Twitter that a new USB-C cable specification has been released. The new spec allows for considerably heftier charging rates between compliant USB-PD devices.

Although Leung points out that the new specification has been under development for two years, very little has changed. Comparing the USB-C 2.0 standard to today's 2.1 standard, the optional new Extended Power Range (EPR) specification—which bumps maximum voltage up to 48 V, sufficient to deliver 240 W at 5 A—seems to be by far the largest change.

From a consumer's perspective, the physical standard hasn't changed—USB-C type 2.1 devices will plug into USB-C type 2.0 ports, and vice versa. Under the hood, the standards on the midplate have gotten stricter—a new paragraph has been added mandating that pins A4-A9 and B4-B9 (power, power delivery, and legacy USB 2.0 support) must not short to ground during connector mating.

Probably the largest amount of added material in the new specification regards the math and engineering considerations for predicting, detecting, and mitigating arcing when unplugging USB-PD cables. (Arcing while plugging them in is not a problem, since high voltages aren't initiated until after the cable is connected.) This isn't a new problem—arcing can become a problem at only 12 V—but the scope for potential damage increases with the new higher voltage possible.

Leave a Comment