DRV8434AEVM: What is the purpose of the capacitors on the motor lines?

Fred Bogardus

Part Number: DRV8434AEVM

I noticed the EVM board has capacitors on the phase traces
leading to ground (C13-C16) I didn't see anything in the documentation
about these? what are these for?

over 3 years ago

0 Wang5577 over 3 years ago

TI__Guru 56650 points

Fred,

C13-C16 are "Do not populate". The EVM reserved space for the EMI performance improvement.

Regards,

Wang Li

0 Fred Bogardus over 3 years ago in reply to Wang5577

Prodigy 30 points

Thank You, do you know where I can learn more about improving the EMI performance?

0 Fred Bogardus over 3 years ago in reply to Fred Bogardus

Prodigy 30 points

Ryan Kehr Do you know of any good application notes on using these capacitors?

+1 Wang5577 over 3 years ago in reply to Fred Bogardus

TI__Guru 56650 points

Fred,

Please check this one https://www.ti.com/lit/ml/slyp697/slyp697.pdf

A 3.3nF output capacitor shows more than 20dB radiation EMI noise reduction.

DRV84xxEVM; 24Vin; 0.6AIFS; 1/16uStep;STRC

Without output 3.3nF:

With output 3.3nF

Regards,

Wang

0 Fred Bogardus over 3 years ago in reply to Wang5577

Prodigy 30 points

The actual presentation is a little more useful. training.ti.com/addressing-emi-challenges-high-side-switches-and-motor-drivers-body-electronics

0 Wang5577 over 3 years ago in reply to Fred Bogardus

TI__Guru 56650 points

Fred,

Thanks,

Wang Li

Motor drivers

Motor drivers forum

DRV8434AEVM: What is the purpose of the capacitors on the motor lines?