DRV2700: How to reduce the output ripple of the flyback circuit

Annie Liu

Part Number: DRV2700

Hi Team,

This is a piezoelectric ceramic power supply with flyback configuration. It has been adjusted to an amplitude of about 150, but the voltage output fluctuation is relatively large. Below is the output and schematic:

Customer would like to know are there any improvements or suggestions?

Thanks,

Annie

over 3 years ago

0 Luis Fernando Rodriguez S. over 3 years ago

TI__Guru* 84915 points

Hi, Annie,

The first thing to try regarding the ripple issue is to increase the output capacitor level. I would suggest to take a look at this E2E thread since it is a similar issue with ~150V output.

https://e2e.ti.com/support/motor-drivers/f/38/t/683015

Please let me know if you have additional observations.

Best regards,
Luis Fernando Rodríguez S.

0 Annie Liu over 3 years ago in reply to Luis Fernando Rodriguez S.

TI__Genius 10295 points

Hi Luis,

With reference to this method, the ripple has been significantly subdivided after the output of the flyback configuration is incorporated into the capacitor. However, there is still a fluctuation of about 300mv in the output, and the ripple cannot be completely removed. May I know is there any suggestion for this?

Thanks,

Annie

0 Luis Fernando Rodriguez S. over 3 years ago in reply to Annie Liu

TI__Guru* 84915 points

Hi, Annie,

You must take into account the capacitance level in the flyback circuit for this case. You would need to try increasing some capacitors values for tuning the flyback circuit until you get the ripple level that you would like to achieve. I would recommend to start with the capacitors C8 and C4. Please start increasing them in 10x multiples and see how it results.

Please let me know if you have additional observations on this.

Best regards,
Luis Fernando Rodríguez S.

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DRV2700: How to reduce the output ripple of the flyback circuit