Qi Components and Subsystems

Components

It is not possible to certify Qi components such as coils, shielding, and ICs. Compliance with the Qi specification can be determined only for products that are completely functional Qi transmitters or Qi receivers.

A product with components that have been used succesfully in a Qi Certified product is not automatically compliant. The use of different housing materials, different locations of coils and shielding, even differences in firmware can interfere with wireless power transfer.

Manufacturers of ICs usually demonstrate the suitability of their IC by certifying a demo product, the so-called "Evaluation Module". Products that use such IC must be tested for compliance. They are not automatically compliant.

Transmitter Subsystems

A subsystem is a completely functional transmitter product, with coils, shielding, and control system assembled together. It can be operated and tested without any additional assembly or construction.

Products with an embedded Qi Certified subsystem need not be tested for compliance with the Qi specifucation, provided the subystem is integrated correctly. Be careful. Incorrect integration, with the wrong coil-surface distance for example, will make the product non-compliant and require testing of product.

You can find a list of Qi Certified Subsystems in the Qi Product Registration Database: "advanced search" and "Subsystem intended for integration into other products" = Yes.

A Tx product can be Qi Certified as a "Subsystem intended for integration in other products" only when it meets these criteria:

  1. The product must includes the means to attach the Tx into the complete system.
  2. The position of coil(s) and shielding relative to the points of attachment must be fixed.
  3. The minimum and maximum distance between the top of the sub-system and the surface of the complete system must be specified.

Example 1: Furniture Charger

Example 2: in-car charger

Example 3: a Tx module

Receiver Subsystems

Products that contain a receiver subsystem, or module, must always be re-tested because materials used in the receiver product are likely to influence foreign object detection.