This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM5145: differences between "LM5145DESIGN-CALC" and "LM5145 Inverting Buck-Boost Quickstart Calculator"

Part Number: LM5145
Other Parts Discussed in Thread: , LM25145, LM5146


On the LM5145 product page both tools are listed. The Excel sheet looks similar, same input boxes. But when filling the sheets with the same requirements and values, I get large differences in resulting required input- and outputs-capacitors, permitted ESR, output capacitor ripple current and efficiency. 

What is the difference between both tools?

And why does the LM5145 product page list both tools, but the LM5145-Q1 page only the first tool?


  • Hi Robert,

    These files are for buck and inverting buck-boost (IBB) topologies, which have different calcualtion for the power-stage components and control loop (bode plot). I will have the IBB file linked to the LM5145-Q1 product folder. Note we also have the LM25145 and LM5146/-Q1 in this family.