What makes a buck power module different from a buck converter? Which device provides the following: better efficiency, smaller solution size, and/or easier PCB layout design? Which one is the better "bang for your buck"? These are some common questions that a customer might have when picking a power management device for their design. The following power module and converter pairs will be used throughout this report: LMR33630/TPSM53603, LMR23630/LMZM33603, and LM5165/TPSM265R1.
Before getting into the side-by-side comparison and tradeoffs of each devices, it is imperative to understand what differentiates a buck converter from a buck power module. Below is bullet-point list of each device's value proposition.
Buck converters feature a controller with one or more integrated power MOSFETs. Customers are required to provide an external power inductor and the remaining components following datasheet recommendation. The buck converter provides the following value proposition:
Buck power modules integrate the converter, power inductor, and additional passive components into one single solution. Customers only need to provide capacitors and in some cases resistors following datasheet recommendation. The buck power module provides the following value proposition:
|Breadth of portfolio||Emerging – fewer options to consider but simplifies device selection||Mature – many options to consider but can be overwhelming|
|Design difficulty (component selection and layout)||Easy||Moderate|
|Solution Size||Smallest||Smallest to Medium (depends on switching frequency, component selection, and layout)|
|EMI||Low without effort||Low - Medium (depends on switching frequency, component selection, and layout)|
|Design Flexibility||Less - Power FET and inductor integrated||Moderate - Power FET integrated|
|Total BOM Cost ($$$ to $)||$$$ to $$||$$ to $|