Charging glossary
Short, precise definitions of the terms that get used loosely in the charging industry. Each definition stands on its own, so it can be quoted without the surrounding page.
The glossary defines the terms that get used loosely in the charging industry, one meaning per term. Each definition is written to be quotable on its own, without the page around it, so a single sentence can be cited accurately out of context. Where the industry uses one word for two different things, both are defined and the entry states which one a given standard means — that is usually the source of a disagreement that looks technical and is actually linguistic. Entries link upward to the full explanation where one exists.
Adjustable Voltage Supply
Adjustable Voltage Supply is the adjustable-voltage mode introduced with the extended power range of USB Power Delivery, operating at higher voltages than PPS.
Baseline Power Profile
The Baseline Power Profile is the original inductive charging profile in the Qi specification, in which the device is placed on a pad without magnetic alignment.
Declaration of Conformity
A Declaration of Conformity is the document in which a manufacturer takes legal responsibility for a product meeting the requirements that apply to it.
Electronically marked cable
An electronically marked cable contains a chip that declares its current and voltage capability to the devices it connects.
Foreign object detection
Foreign object detection is the safety function that stops a wireless charger when a metal object other than the intended receiver is present on the charging surface.
Gallium nitride
Gallium nitride is a wide-bandgap semiconductor used in power conversion, allowing smaller and more efficient chargers at high switching frequencies.
IEC 62133-2
IEC 62133-2 is the international safety standard for portable sealed lithium cells and the batteries made from them.
Magnetic Power Profile
The Magnetic Power Profile is the part of the Qi2 specification that governs magnetically aligned wireless charging between a transmitter and a receiver.
NRTL
An NRTL is a laboratory recognised by the US occupational safety regulator to test and list products against US safety standards.
Power Data Object
A Power Data Object is one entry in the list of voltage and current combinations that a USB Power Delivery source advertises to a device.
Power range
Standard Power Range and Extended Power Range are the two power tiers of USB Power Delivery, split at 100 W and using different voltage sets.
Programmable Power Supply
Programmable Power Supply is the adjustable-voltage mode within USB Power Delivery that lets a device request fine voltage steps rather than a fixed level.
Qi
Qi is the wireless power transfer specification published by the Wireless Power Consortium, covering inductive charging of phones, wearables and accessories.
Qi2
Qi2 is the current generation of the Wireless Power Consortium's wireless charging specification, adding a magnetic attachment profile to the existing inductive profiles.
Rated capacity
Rated capacity is the minimum charge a battery is guaranteed to hold, as distinct from the higher typical capacity quoted in marketing.
UN 38.3
UN 38.3 is the test regime that lithium cells and batteries must pass before they may be transported, covering altitude, thermal, mechanical and electrical abuse.
USB Power Delivery
USB Power Delivery is the protocol that lets a USB-C charger and a device negotiate voltage and current instead of relying on a fixed default.
Watt-hour rating
Watt-hour rating is the energy a battery holds, and it is the figure that determines which transport and aviation rules apply to a product.
One meaning per term
Where the industry uses a word for two different things, the glossary defines both and says which one a given standard means. That is usually the source of a disagreement that looks technical and is actually linguistic.
Wireless power
Inductive coupling, magnetic alignment, foreign object detection, thermal derating, and the difference between a specification and a certification.
Wired power
Power delivery contracts, power data objects, PPS, e-marked cables, and what a wattage rating does and does not guarantee.
Batteries and compliance
Rated capacity, watt-hour limits, transport testing, and the vocabulary of conformity and certification.