40-W 5-V single-switch forward converter with magnetic feedback reference design


Design files


This reference design generates an isolated 5-V at 40-W from a 60-V to 120-V DC-input voltage. The design uses a magnetic feedback circuit to replace the function of an optocoupler.

  • Use of 100-krad ICs and magnetics
  • Magnetic feedback used to replace optocoupler
  • Operation with external supply or self-bias
Output voltage options PMP23033.1
Vin (Min) (V) 60
Vin (Max) (V) 120
Vout (Nom) (V) 5
Iout (Max) (A) 8
Output Power (W) 40
Isolated/Non-Isolated Isolated
Input Type DC
Topology Forward- Integrated Switch

A fully assembled board has been developed for testing and performance validation only, and is not available for sale.

Design files & products

Design files

Download ready-to-use system files to speed your design process.

TIDT268.PDF (1119 K)

Test results for the reference design, including efficiency graphs, test prerequisites and more

TIDMA78B.PDF (194 K)

Detailed schematic diagram for design layout and components

TIDMA79.PDF (170 K)

Complete listing of design components, reference designators, and manufacturers/part numbers

TIDMA80.PDF (244 K)

Detailed overview of design layout for component placement

TIDMA82.ZIP (1370 K)

Files used for 3D models or 2D drawings of IC components

TIDCG54.ZIP (764 K)

Design file that contains information on physical board layer of design PCB

TIDMA81.PDF (866 K)

PCB layer plot file used for generating PCB design layout


Includes TI products in the design and potential alternatives.


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PWM controllers

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Shunt voltage references

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Technical documentation

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Type Title Date
Test report 40-W, 5-V, Single-Switch Forward Converter With Magnetic Feedback Ref. Design PDF | HTML Mar. 28, 2022

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