This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ51050B: Small 20*20mm TDK WR202010-18M8-ID Coil

Part Number: BQ51050B
Other Parts Discussed in Thread: BQ51010B, TIDA-00318

Hello,,

I have received this reply from a TDK applications engineer:

"You cannot use the WR202010-18M8-ID with this design as it is written. The bq51010b is for use with a Qi compliant Tx coil which this 20 mm round Rx coil will have a lot of difficulties using due to the physical size mismatch. I know TI has other chipsets which are geared for lower power applications and use a smaller Tx coil. Additionally, this coils is modified to be optimized with an IDT chipset so the inductances are not quite what the TI chipset may require. But you can discuss with TI."

(1) Will this coil work with this chipset? We require this small coil. If not, is there another solution?

(2) Does this coil which is "optimized for IDT chipset" have suitable inductance for this TI chipset?

Thanks,

Billy

  • Hi Billy
    Take a look at TIDA-00318 and TIDA-00329, they have test data on the TDK WR222230-26M8-G which is a 22mm coil with L value of 27uH. The above coil has an L value of 18uH and that may be a little low.
  • Hi Bill,

    Thank you for your response, much appreciated. TIDA-00329 does not contain information on component values for inductor matching or FOD circuits, but TIDA-00318 does. So, what I am doing as the first pass for my PCB is copying the values from TIDA-00318 for the inductor matching circuit, but am following the placeholder recommendations from the BQ51010b data sheet for the FOD area of the circuit, and will tune this according to my end product configuration. There isn't much information available for tuning the FOD, can you recommend the best method for it?

    Many thanks,

    Billy

  • Hi Billy
    The coil tuning and FOD tuning are treated separately.
    First step would be to get the RX Coil tuned and this needs to be done on the TX coil and with your RX case. See Series and Parallel Resonant Capacitor Section of data sheet.

    FOD tuning procedure is a last step. Use placeholder values from EVM or TIDA. Files for this are located in the bq51010B page under tools & software.