LM5122: pmp10749 boost converter with dual phase

Electronx Electronx

Part Number: LM5122
Other Parts Discussed in Thread: PMP10749,

Hi! I need to design a boost convert the specs with

Application Field : Cold Crank (start stop)

Required Specs for the application : In case of cold crank, the input voltage can drop to 3 volts.So 3 volt and higher input voltage value is required in accordance with this situation.

Vout: 10V output and up to 20A.

I'm trying to create a boost converter with the requirements I mentioned above. I realized that the boost converter in the design of the pmp10749 fits my requirements, However, its 10Amp output is insufficient, so I need a dual phase design. However, I don't know exactly what changes I need to make. How should I connect the syncout pin? ? Do I need to make any changes to the compensation elements? Do I need a change in the capacitor connected to the bst pin?

or other elements ?

over 1 year ago

+1 Stefan Schauer over 1 year ago

TI__Mastermind 46341 points

Hi,

please check the datasheet for more information about this.

Good starting points are:

7.4.4 Slave Mode and SYNCOUT
8.1.3 Interleaved Boost Configuration
Figure 31. Dual Phase Interleaved Boost Configuration

Compensation needs to be adjusted for your application configuration with max output current divided by power stages.

No need to change the capacitor on the BST pin. The driver of the LM5122 still does only need to drive one high side FET.

Best regards,

Stefan

0 Electronx Electronx over 1 year ago in reply to Stefan Schauer

Intellectual 285 points

Hi Stefan! Thanks for your help, as in the picture it can be seen that the Syncout pin of the master IC goes to the SYNC /RT pin of the slave IC. "Compensation needs to be adjusted for your application configuration with max output current divided by power stages." What kind of calculation should I do here? Can't I use the values of compensation elements calculated for single phase ? And are there any other changes I need to make?

+1 Stefan Schauer over 1 year ago in reply to Electronx Electronx

TI__Mastermind 46341 points

Hi,

yes, you can use the compensation for a single phase with halve the output current. So, for what one stage needs to handle.

Best regards,

Stefan

+1 Stefan Schauer over 1 year ago in reply to Stefan Schauer

TI__Mastermind 46341 points

Hi,

as we have not received an additional information, I assume this issue is solved and I am closing the thread.
If there is still something open, just reply to open it again or open a new thread.

Best regards,
Stefan

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LM5122: pmp10749 boost converter with dual phase