PMP7969: LM5122

Shinu, hello and thank your for your inquiry. Can you provide more information on what you are requesting? Are you wanting to have the PMP7969 board assembled and sent to you for customer evaluation OR are you wanting additional information on the design that is not in the current test report?

Best Regards,
John Fullilove
Manager, TI Design

Hi Shinu,

The design files can be found on the PMP7969 webpage under the design files link. All the available data is in the test data document.

Thanks,

Garrett

Hello Team,

Sorry for the delay in response. We required calculation file of PMP7969, 4 phase design. We would like to understand the chosen inductor and Mosfet selection parameters for this design. 

Regards, Shinu Mathew.

Hello Team,

PMP7969 test data shows one phase is loaded with full power for short period of time (refer attached dig). Can you please help with your comments on the same.

LM5122-2 PMP7969.pdf

Regards,

Shinu Mathew

Hello Team,

Can you please help on this.

Regards, Shinu Mathew.

Hi Shinu,

The component values were selected using the equations in the datasheet. The inductor value can be calculated using equation 26 of the datasheet.

Can you please clarify what issue you are running into on the waveform that you provided? This looks like normal operation with all 4 phases shifted by 90 deg to achieve interleaved operation.

Thanks,

Garrett

Hi Shinu,

I don't quite understand your question? The waveform you attached shows all 4 phases are switching and running full load, I don't see an issue.

I agree with Garrett, the inductor selection is based on Fsw and ripple current. The FET selection is based on the max Vout voltage plus some margin, this will determine the necessary Vds rating of the FET in a boost config. Qg and Rdson of the FETs will determine the losses on the FETs.

Best regards, Max

Hello Team,

Thanks for the support.

I would like to know the avaliablity of design file (design calcuations) other than the schematic, wave forms and pcb files.

Regards, Shinu

Hi Shinu,

The design files such as the schematics and the test report can be found on the PMP7969 webpage. The design equations were just done following the LM5122 datasheet equations.

Thanks,

Garrett

Hi Garrett,

Thanks for the support.

Regards, Shinu Mathew