What power classes exist for USB-C?

Power classes (wattage):

The charging power varies depending on the charger, cable, and device used:

Up to 15 watts: The basic standard (5V / 3A). Ideal for small devices like headphones or smartwatches.

Up to 100 watts: The standard for USB-PD. Sufficient for most tablets, office laptops, and phones.

Up to 240 watts (EPR): Extended Power Delivery standard. Designed for extremely high-performance gaming laptops and workstations.

The most important charging protocols:

Charging power is controlled by protocols that dynamically adjust power output and voltage:

USB Power Delivery (USB-PD): The cross-industry standard (supported by Apple, Android, Windows).

PPS (Programmable Power Supply): An extension of USB-PD. Adjusts the voltage in real time to reduce heat generation and battery damage.

Manufacturer-specific protocols: Technologies such as Qualcomm Quick Charge, Samsung AFC, or Huawei SuperCharge. Often only usable at maximum speed with the respective original power supply.

Important practical tips:

Not every USB-C cable is the same: To transfer high wattages (e.g., over 60W), the cable often needs to contain a special E-marker chip. Therefore, always check the manufacturer's specifications when purchasing.

Cable length: Very long cables (over 2 meters) can reduce charging performance due to higher electrical resistance.

Safety: Thanks to intelligent communication between the power supply and the end device, you can easily charge your phone with a powerful laptop power supply. The device only ever draws as much current as it can actually process.