Bluetooth Qualification Process - Who determines if circuit changes are "minor"?

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RoRo_3281831
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We are looking into using a PSoC 4 BLE device in our designs.  We would like to place the PSoC 4 chip directly onto our own PCB.  Of course, we'd like to avoid having to qualify our design as a new design to Bluetooth SIG - we'd rather just use the relevant QDID, like those listed here: https://community.cypress.com/docs/DOC-13885

However, the documentation that talks about when you can use another QDID or if you have to get your own is somewhat unclear.  Of course, for a fully qualified module, it is clear that you can simply use the module's QDID.  But when using a "silicon" solution and then providing your own circuit board/antenna, the documents are full of non-committal wording such as "may have to test" or "if the changes are minor", etc, etc.  So my question is - who determines the answer to these questions?  Do we self-certify that we followed the qualified design guidelines (if such guidelines even exist), and then just apply for a declaration and listing?  Or do we submit the design to some authority?

For example, the document "Process for Qualifying a Bluetooth Product" (https://community.cypress.com/docs/DOC-9293) almost answers my question in paragraph 1.2, Scenario 1, where it states (bold red emphasis mine):

Scenario 1 – Using the silicon and referencing Cypress’s End Product QDID for silicon

In this case, you do one or more of the following:

  1. Using the BLE modules supplied with Cypress’s BLE Pioneer Kit in your product.
  2. Referencing the schematics and layout provided for the BLE modules supplied with Cypress’s BLE pioneer Kit.
  3. Making minor changes to the electrical circuit with the assessment confirming that the changes do not change the compliance status of the design, or making changes to the electrical circuit and confirming that the compliance is not impacted by running the RF/PHY tests at a BQTF.

So, who is confirming this assessment?  Clearly, we have due diligence to perform our own design assessment, but surely there must be some way to demonstrate that this has been accepted by the certifying authority.

In general, can we just use the required silicon device, follow design guidance (such as http://www.cypress.com/documentation/application-notes/an91445-antenna-design-and-rf-layout-guidelin...), and place the rest of our circuitry on the PCB located sufficiently far away from the RF section?

We are trying to plan our design cycle for incorporating bluetooth, and for space constraint reasons we would like to avoid purchasing an additional module, but want to avoid extensive testing time and fees.

I apologize if this has been asked and answered, but in all my searching on this website I haven't found anything definitive.

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1 Solution
GuhapriyanT_31
Employee
Employee
10 solutions authored 25 replies posted 10 replies posted

Hi rroth_3281831,

Q: So, who is confirming this assessment?  Clearly, we have due diligence to perform our own design assessment, but surely there must be some way to demonstrate that this has been accepted by the certifying authority.

A: When we talk about changes to the design,  most of the required circuit for Bluetooth operation are inside the PSoC4BLE. The one which are outside of it and can affect the BLE performance are the layout, power supply (including decaps), crystal selection and tuning, matching network, RF trace to the Antenna and the Antenna.

As long as the changes confirm to the guidelines mentioned in our application notes AN91445 and AN95089, the design should work just fine.

The assessment can be done by your own expert in addition to internal conducted testing of critical parameters such as output power and frequency offset. If these parameters are withing the datasheet specification, the change can be considered minor and you can still use the QDID of Cypress. If you are not sure, you can send the design to Cypress through a CRM case for review.

Thanks,

Guha

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GuhapriyanT_31
Employee
Employee
10 solutions authored 25 replies posted 10 replies posted

Hi rroth_3281831,

Q: So, who is confirming this assessment?  Clearly, we have due diligence to perform our own design assessment, but surely there must be some way to demonstrate that this has been accepted by the certifying authority.

A: When we talk about changes to the design,  most of the required circuit for Bluetooth operation are inside the PSoC4BLE. The one which are outside of it and can affect the BLE performance are the layout, power supply (including decaps), crystal selection and tuning, matching network, RF trace to the Antenna and the Antenna.

As long as the changes confirm to the guidelines mentioned in our application notes AN91445 and AN95089, the design should work just fine.

The assessment can be done by your own expert in addition to internal conducted testing of critical parameters such as output power and frequency offset. If these parameters are withing the datasheet specification, the change can be considered minor and you can still use the QDID of Cypress. If you are not sure, you can send the design to Cypress through a CRM case for review.

Thanks,

Guha