BQ51013 - PCB coil

Ido Baruch

Other Parts Discussed in Thread: BQ51013B

Hello,
I want to insert the coil circuit as one of the layers of the PCB is it possible?
What is the minimum inductance of the coil (for 100 - 200mA)?
Can I get examples of these coils?

Thank you,

Ido

over 13 years ago

0 Bill Johns over 13 years ago

TI__Guru* 75806 points

PCB coils are possible, we are testing some versions. A shield will be required behind the coil.

The inductance should be between 10uH to 15uH, this is with the complete stack up using WPC test fixture and battery.

Can you describe the size of coil you will use or area you have available for the coil?

0 Fernando Vega over 11 years ago in reply to Bill Johns

Prodigy 30 points

Hi, what would be your recommendation for a 25x25mm area? Thanks

0 Reinhard Koeppner over 11 years ago in reply to Bill Johns

Prodigy 185 points

Hi there,

is the shield behind the coil strictly necessary?

Did you find some geometrical suggestions for an board are of around 25x25mm?

Thanks in advance,

Reinhard

0 Dick Stacey over 11 years ago in reply to Reinhard Koeppner

TI__Genius 14890 points

Reinhard,

The coil shield for the bq51013B is required. The shield is used to contain and optimize the magnetic field created by the transmitter. Without the shield, the energy created by the power transmitter field would be absorbed by other material and could cause heating or other unwanted results.

Regards,

Dick

0 Dick Stacey over 11 years ago in reply to Fernando Vega

TI__Genius 14890 points

Fernando,

Can you be more specific with your question?

Regards,

Dick

0 Fernando Vega over 11 years ago in reply to Dick Stacey

Prodigy 30 points

Thanks Dick, this is relatively the same scenario described by Ido at the beginning of this post.

Do you have any recommendations to design a PCB coil (in a 25x25mm area) to charge a 150mAh Lipo Battery?

Thanks,

Fernando

0 Dick Stacey over 11 years ago in reply to Fernando Vega

TI__Genius 14890 points

Fernando,

I have no specific recommendations, but some things to be aware of. In general, a PCB coil will be lower in efficiency than a standard coil. Your charge current will be relatively low so this may not be a huge impact. The resonant capacitors must be tuned to the specific coil you are using. Work closely with the PCB coil manufacturer to understand their process and what to expect from the inductance and resistance.

Regards,

Dick

0 Abhishek K over 10 years ago in reply to Dick Stacey

Prodigy 60 points

Hello Dick, Do you know any service providers for WPC coil designers on PCB?
It will be good help if you can give us list of contact.
If not possible, is TI having any PCB coil design model?

0 Bill Johns over 10 years ago in reply to Abhishek K

TI__Guru* 75806 points

Hi Abhishek
We do not have PCB coils or a supplier for PCB coil. TDK has worked with TX PCB coil and can possibly help.
The work I have done with PCB RX coils shows a higher loss due to DC resistance of the etch even with thick copper. May have an application in lower power, 500mW or less.

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BQ51013 - PCB coil