LM5146: Two LM5146 in parallel - SIMetrix simulation

Ryan Rah

Part Number: LM5146
Other Parts Discussed in Thread: LM5190

Tool/software:

Hi,

Considering LM5146, I am interleaving two of buck converters sharing a load.

When I run the simulation and set the battery target to 30V, which is the same target output voltage for both converters, the output voltage is going almost double!!

If I run each buck independently under 30V target output voltage, they work well and converge to 30V after almost 4ms but as soon as I parallel them and set target to 30V for both, they are acting weird!

5 months ago

0 Timothy Hegarty 5 months ago

TI__Guru 72722 points

Hi Ryan,

There is no inherent current sharing with a voltage-mode control architecture, such as the LM5146. Consider using the LM5190 80V current-mode controller, especially if the end application is battery charging (as this controller has CC/CV functionality specifically for that purpose).

Regards,

Tim

0 Ryan Rah 5 months ago in reply to Timothy Hegarty

Prodigy 180 points

Timothy,

knowing that, I need to analyze the circuit!

0 Timothy Hegarty 5 months ago in reply to Ryan Rah

TI__Guru 72722 points

Ryan,

As mentioned, the LM5190 is the recommended solution here, not the LM5146. What is the required output current? One phase may be sufficient.

You can use the quickstart calculator as a starting point. I may have a SIMPLIS model for the LM5190 as well.

Regards,

Tim

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LM5146: Two LM5146 in parallel - SIMetrix simulation