3.3V/15A Active Clamp Forward Reference Design


Design files


This reference design is a 50W active clamp forward converter with synchronous rectification on the secondary side. The design provides an isolated, 3.3V/15A output from a standard telecom -36V to -72V input at >91% efficiency. PMP20850 utilizes a self driven, synchronous rectifier which requires no secondary gate driver which minimizes cost and improves efficiency. This device also features programmable dead-time, which is fine tuned to maximize efficiency of the design. Output voltage regulation is based on current mode control, simplifying loop compensation. PMP20850 features a catalog transformer, minimizing the cost of magnetics in the design.

  • >90% efficiency with 15A load across full input voltage range
  • Self driven synchronous rectifier eliminates need for secondary gate drivers
  • Catalog transformer minimizes cost of magnetics
Output voltage options PMP20850.1
Vin (Min) (V) -72
Vin (Max) (V) -36
Vout (Nom) (V) 3.3
Iout (Max) (A) 15
Output Power (W) 49.5
Isolated/Non-Isolated Isolated
Input Type DC
Topology Forward- Active Clamp
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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.

TIDUDA9.PDF (1929 K)

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


Detailed schematic diagram for design layout and components


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


Detailed overview of design layout for component placement

TIDRRF3.ZIP (1154 K)

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


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


PCB layer plot file used for generating PCB design layout


Includes TI products in the design and potential alternatives.

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Technical documentation

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Type Title Date
* Test report PMP20850 Test Results Jun. 19, 2017

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