DRV8662EVM: Change DRV8662 output Vpp fail

Dears, TI team

   question 1: DRV8662 boost efficiency?

   question 2 :How to calculate  the output power consumption while the load is a piezoelectric ceramic?(PS:the current phase lead voltage 90° )

     question3: how to increase the P( S2=P2+Q2)?

 the test picture as below:

the input for the DRV8662EVM board is USB 5V:

Dear, Ti teams

   I have a question when I test the power consumption of DRV8662 and  piezoelectric ceramics. The question was described in the bellow picture.

   there was a current pulse on the output current signal, which has the same frequency with the boost DCDC PWM signal, is it normal? how can I improve it?

Hello, 

The image you added is not showing up properly for me. Can you please re-upload it and make sure you are using the insert media or insert file button rather than pasting the image into the reply. 

Thank you, 

Justin Beigel

Hello, 

Thank you for re-uploading the image. We are looking into this now and will get back to you as soon as possible. 

Best Regards, 

Justin Beigel

Dear，Justin

   Is there any progress on this issue?

Hello, 

With the frequency showing up on the Vout_N trace, does it still show up if you take the differential output (Vout_P - Vout_N)? 

Best Regards, 

Justin Beigel

Dear,Justin

   The VPP(Vout_P - Vout_N) is clear and without PWM wave. 

Best regards,

philips

Dear,Justin

   The VPP waveform is OK，but there are still  current pulse and voltage pulse on the output, that is normal?

Hello, 

Since the Vpp waveform is okay, this is working as expected. The pulses on the voltage lines should always cancel out when looking at the differential ouptut. 

Best Regards, 

Justin Beigel

Dear,Justin

   So there is no method to improve or eliminate the current pulse to the piezoelectric ceramics?