Myountek — USB-C Cables and Charging Power | myountek.com
Four connector facts to check on any USB-C plug or cable before trusting its power rating.
USB-C is a 24-pin reversible connector whose specification was published in August 2014. The pin layout is mirrored across the plug, which is what allows the connector to seat in either orientation.
The earlier USB connectors were designated legacy in 2014, the same year the USB-C specification appeared. Older plugs remain in use, but the specification treats them as legacy rather than current.
The USB4 specification, released in 2019, is the first USB protocol standard that applies exclusively over USB-C. No other connector carries USB4, so a USB4 device necessarily uses this plug.
On narrow screens, swipe or scroll the plate sideways.
Cable identity is handled by an E-Marker chip. All USB Type-C cables except the minimal USB 2.0 and 3 A combination must contain one, and the chip reports the cable's current and data rating to the charger.
The practical consequence: a cable without an E-Marker is capped at the minimal combination. Anything claiming higher data rates or more than 3 A of current must carry the chip, and packaging that omits both claims should be read as the minimal combination.
Reversibility, pin count, publication date and E-Marker presence are the four facts printed or measurable on any plug — together they determine whether a cable can carry the wattage your charger outputs.
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