RE: LM25118: Digitally controlled Buck converter simulation

Hi Guillaume,

I have split this into a new thread to get the attention of the apps engineer supporting the LM25118. Here's a link to the previous post for more context.

https://e2e.ti.com/support/power-management/f/196/t/906341

Hi Guillaume,

Thanks for considering the LM25118 in your design.

Are the specifications the same as the other post? The LM25118 quick-start calculator can be used to calculate the correct components. This is similar to the excel sheet that Anthony provided you in the other post.

Please let me know if you have any questions.

thanks,

Garrett 

Hi Garrett,

Thank you for the calculator. In this case the specs are a quite different, the input voltage is still 12V, but the output voltage should be set from 3V to 22V, with 5A as the maximum input current.

As the 12V power supply I used can only supply up to 60W, I won't use 5A for the whole output voltage range.

Best regards,

Guillaume

Hi Guillaume,

The LM5118 should work for these design parameters. What is the application? Is it USB-C related?

Do you need to limit the input current? 

Thanks,

Garrett

Hi Garrett,

Yes it is a power supply for USB-C validation testing.

It could be useful to limit the output current, for now I considered using a power monitor that could alert an MCU in case of an abnormal output current or voltage situation.

Best regards,

Guillaume

Guillaume,

For USB-C-PD the maximum output voltage should be 20V. If your application the can live with ~21V on the output the TPS55288 might be a better option. this has the current limiting function included and has an I2C interface if needed. There is also a version without the I2C interface.

Thanks,

Garrett

Hi Garrett,

I want to be able to go over 20V just in order to test the OVproctection on our devices, so 21V will do.

The TPS55288 looks perfect for what I want to do, my only concern is that it is actually in preview, and the PCB I'm designing will be launched into production in the following weeks.

Do you know how I could get some by this time ?

Best regards,

Guillaume

Guillaume,

Let me me loop in the engineer that is supporting this device. He should be able to help regarding the time line of the device.

Thanks,

Garrett

Hi Helen,

for our design the I2C link is needed. Will the sample be available directly on the device's page ?

Regarding stability condition is there a way I can check the circuit would remain stable for the whole output voltage range ? I saw that an EVM of the device was released, so I am planning to use the same design.

Best regards,

Guillaume

Hi Garrett,

I am trying to edit the spreadsheet but a password is requested, could you please send it to me ?

Best regards,

Guillaume