50V to 5V @7A Synchronous Buck (Step-down) Converter

  • Rajkumar Sharma
  • 2633
  • medium
  • Tested

This module is a non-isolated 7A DC-DC converter. The module can convert any DC voltage between 7V to 50V to a 5V DC with load current up to 7A. The project has been designed around LM5116 Wide Range Synchronous Buck Controller IC. The design includes 6uH toroid inductor and two N channel MOSFETS. The operating frequency is 250 KHz.

The LM5116 is a synchronous buck controller intended for step-down regulator applications from a high-voltage or widely varying input supply. The control method is based upon current mode control utilizing an emulated current ramp. Current mode control provides inherent line feed-forward, cycle-by-cycle current limiting, and ease-of-loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high-input voltage applications.

The operating frequency is programmable from 50 kHz to 1 MHz and the LM5116 drives external high-side and low-side NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables discontinuous operation mode, for improved efficiency at light load conditions. A low quiescent current shutdown disables the controller and consumes less than 10 µA of total input current.

Additional features include a high-voltage bias regulator, automatic switch-over to external bias for improved efficiency, thermal shutdown, frequency synchronization, cycle-by-cycle current limit, and adjustable line under-voltage lockout. The device is available in a power enhanced HTSSOP-20 package featuring an exposed die attach PAD to aid thermal dissipation.


  • Wide Operating Range 7V – 50V
  • Output 5V DC
  • Load Current Up To 7Amps
  • Thermal Shutdown
  • Operating Frequency 250Khz
  • PCB Dimensions 45.04 x 22.82 mm


Parts List



LM5116 Datasheet



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Sagheer Ahmad

50V to 5V @7A Synchronous Buck (Step-down) Converteri am from Pakistan And i am PCB designer work at home design suit easy-Eda online easy-PC v15 and others i like your All Synchronous Buck (Step-down) Converter.Please Help me send value 50V to 5V @7A component list R5,C7,C9 and not found EASY EDA 6UH 10A torrid inductor coil


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