Internship test

Buck-Converter

A step-down DC-DC converter design using the Texas Instruments LMR51450SDRRR switching regulator IC.

Overview

This buck converter circuit is designed to efficiently convert a higher input voltage to a lower, regulated output voltage. The design features the LMR51450SDRRR IC which provides excellent efficiency and thermal performance in a compact package.

Specifications

• Input Voltage Range: 3.8V to 36V
• Output Voltage: 7.6V
• Maximum Output Current: 4A
• Switching Frequency: ~2.1MHz (configurable)

Bill of Materials (BOM)

The BOM details can be found in BOM.csv

Estimated Total Cost: ₹558.00 (Indian market pricing)

Files

• BOM.csv - Complete bill of materials with pricing
• buck-converter.kicad_sch - KiCad schematic file
• buck-converter.kicad_pcb - KiCad PCB layout file

Schematic

You can view the schematic from the KiCad project files or export it as a PDF for documentation purposes.

PCB Layout Considerations

• Thermal Management: Adequate copper pour for heat dissipation
• EMI Reduction: Proper grounding and component placement
• Current Handling: Wide traces for high-current paths
• Component Placement: Critical components placed close to the IC

Design Notes

• Feedback resistors (RFBB1, RFBT1) set the output voltage
• Compensation network (RFF1, CFF1) ensures stable operation
• Bootstrap capacitor (CBOOT1) drives the high-side MOSFET
• Input/output capacitors provide filtering and energy storage

Testing and Validation

Before deployment, ensure to test:

• Output voltage regulation
• Load transient response
• Thermal performance
• EMI compliance
• Efficiency measurements

References

• LMR51450SDRRR Datasheet
• TI Application Notes for buck converter design
• KiCad Design Rules for high-frequency switching circuits