SNVA988 August   2020  – MONTH  LMZM33603 , TPSM265R1 , TPSM53603


  1.   Trademarks
  2. 1Introduction
  3. 2Efficiency and PCB Solution Size Comparison
  4. 3Considerations When Using Converters and Power Modules
  5. 4Summary
  6. 5References


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:

  • Easier to implement than a buck controller which does not have integrated power MOSFETs
  • More design flexibility and optimization to design specification than a power module
  • Lower total solution cost than a power module

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:

  • Highest level of component integration simplifies and reduces customer bill-of-material
  • Greatly reduces time and cost to market by lessening power design time
  • System level solution (All internal components: inductor, capacitor, resistor, and so on) are qualified per Texas Instruments' standards
  • Optimized for electro-magnetic interference, thermal performance, and operational stability
Table 1-1 Summary of Power Module and Converter Highlights
Power ModuleConverter
Breadth of portfolioEmerging – fewer options to consider but simplifies device selectionMature – many options to consider but can be overwhelming
Design difficulty (component selection and layout)EasyModerate
Solution SizeSmallestSmallest to Medium (depends on switching frequency, component selection, and layout)
EMILow without effortLow - Medium (depends on switching frequency, component selection, and layout)
Design FlexibilityLess - Power FET and inductor integratedModerate - Power FET integrated
Total BOM Cost ($$$ to $)$$$ to $$$$ to $