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.
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.
A Tx product can be Qi Certified as a "Subsystem intended for integration in other products" only when it meets these criteria:
The product must includes the means to attach the Tx into the complete system.
The position of coil(s) and shielding relative to the points of attachment must be fixed.
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
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.
Products with an embedded Tx subsystem
Products that contain an embedded Tx subsystem can be registered with a simplified procedure. Testing of the product is not required when the product meets these criteria:
Brand name and type-number of the sub-system must be clearly visible on the sub-system.
Brand name and type-number of the sub-system do not have to visible on the system. Disassembly of the system may be need to determine brand name and type-number of the sub-system.
The sub-system must be in the product registration database with this brand name and type number.
The distance between the top of the sub-system and the surface of the complete system is within the tolerances specified during registration of the sub-system.
The power supplied to the sub-system must meet the specified minimum level.
Materials used in the complete system between the sub-system and the surface of the complete system do not influence the magnetic field.