DRV8212: Advice for using DRV821x for inductive power transfer

Bryan McLaughlin

Part Number: DRV8212
Other Parts Discussed in Thread: DRV8812, DRV8412

Tool/software:

Hello - I'm designing a non-standard, 2W inductive power system that will operate in the 100-1000kHz range. I'll probably used a fixed frequency and adjust the supply voltage (VM) to adjust the output power.

The DRV8212 and similar parts seem like a nice compact solution for driving the inductive transmit coil.

Do you have any advice on potential issues and pitfalls with driving an inductive coil with the DRV821x?

Thanks!

9 months ago

0 Bryan McLaughlin 9 months ago

Expert 1110 points

I just realized the DRV8812 only goes to 100kHz. The same question applies though...

Let me know if you have alternative integrated H-bridge parts that could be suitable for higher frequencies. Thanks!

+1 David Medis 9 months ago in reply to Bryan McLaughlin

TI__Genius 17510 points

Hi Bryan,

Yes, the DRV8212 can drive an inductive coil. Using independent half-bridge control will allow you full control of the load by being able to configure high-side or low-side switching.

The following app note goes into detail about the specifics of driving solenoids, and the advantages of using TI's motor drivers to drive them.

Using DRV to Drive Solenoids (Rev. A) (ti.com)

Best,

David

0 Bryan McLaughlin 9 months ago in reply to David Medis

Expert 1110 points

Thanks David. I also came across this app note which was helpful.

I would want to add freewheeling diodes between OUT1-GND and OUT2-GND to protect the DRV during the switching transitions. Any recommendations for diode type/specs? I would want the external diodes to bear more burden than the DRV low-side FET body diodes. Thanks.

0 David Medis 9 months ago in reply to Bryan McLaughlin

TI__Genius 17510 points

Hi Bryan,

If you are wanting to add additional freewheeling diodes than just a traditional diode, within voltage and current specs, will do. If you are wanting to dissipate current faster by clamping the output, then a TVS or Zener diode would be better.

Best,

David

0 Bryan McLaughlin 9 months ago in reply to David Medis

Expert 1110 points

Thanks David. Final question: what DRV H-bridge devices have the fastest switching frequency?

0 Shinya Morita 9 months ago in reply to Bryan McLaughlin

TI__Mastermind 41885 points

Thank you for your question. Monday September 2nd is national holiday in US. Will support your post when back to office.

+1 David Medis 9 months ago in reply to Bryan McLaughlin

TI__Genius 17510 points

Hi Bryan,

Most of our motor drivers are in the 100kHz to 200kHz range, however, some devices like the DRV8412 go up to 500kHz.

DRV8412 data sheet, product information and support | TI.com

Best,

David

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DRV8212: Advice for using DRV821x for inductive power transfer