36V-75Vdc Input, 5V/50W 1/8 Brick Active Clamp Forward Reference Design
This product has been released to the market and is available for purchase. For some products, newer alternatives may be available.

Description & Features

Technical documentation

Support & Training

Order Now

See the Important Notice and Disclaimer covering reference designs and other TI resources.


This reference design generates a 5V/10A output from a standard telecom 48V DC input. The UCC2897A controls an active clamp forward converter power stage. The low gate charge and low RDSon of the CSD17309Q3 and CSD18540Q5B, implemented as self-driven synchronous rectifiers, allow this design to achieve a max load efficiency over 93%.  This design uses only ceramic output capacitors for high reliability and uses 100% surface mount components.  The board is laid out on a standard eighth brick footprint.

  • Industry standard 1/8 Brick Footprint, 0.9" x 2.3" (23mm x 58mm)
  • High efficiency (greater than 93%)
  • All ceramic output capacitors
  • Self-driven synchronous rectifiers reduce drive complexity
  • 100% surface mount components
  • Low profile - 0.35" (9mm) maximum top side component height

See the Important Notice and Disclaimer covering reference designs and other TI resources.


Schematic/Block Diagram

Quickly understand overall system functionality.

Download Schematic

Test Data

Get results faster with test and simulation data that's been verified.

Download Test Data

Design Files

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

Download Design Files

(Output Voltage 1)
Vin (Min) (V)36
Vin (Max) (V)75
Vout (Nom) (V)5
Iout (Max) (A)10
Output Power (W)50
Input TypeDC
TopologyForward- Active Clamp
Forward- Synchronous

TI Devices (3)

Order samples, get tools and find more information on the TI products in this reference design.

Part Number Name Product Family Sample & Buy Design Kits & Evaluation Modules
CSD17309Q3  30V, N ch NexFET MOSFETâ„¢, single SON3x3, 6.3mOhm  MOSFETs  Sample & Buy View Design Kits & Evaluation Modules
CSD18540Q5B  60V, N ch NexFET MOSFETâ„¢, single SON5x6, 2.2mOhm  MOSFETs  Sample & Buy View Design Kits & Evaluation Modules
UCC2897A  110-V active clamp current mode PWM controller with P-channel clamp FET and line OV protection  Offline & isolated DC/DC controllers & converters  Sample & Buy View Design Kits & Evaluation Modules

CAD/CAE symbols

Part # Package | Pins CAD File (.bxl) STEP Model (.stp)
CSD17309Q3 VSON-CLIP (DQG)| 8 Download Download
CSD18540Q5B VSON-CLIP (DNK)| 8 Download Download
UCC2897A Download Download
Download Download

Texas Instruments and Accelerated Designs, Inc. have collaborated together to provide TI customers with schematic symbols and PCB layout footprints for TI products.

Step 1: Download and install the free download.

Step 2: Download the Symbol and Footprint from the CAD.bxl file table.

Technical documentation

See the Important Notice and Disclaimer covering reference designs and other TI resources.

User guides (1)
Title Type Size (KB) Date
PDF 3971 10 Sep 2014
Design files (6)
Title Type Size (KB) Date
ZIP 214 10 Sep 2014
ZIP 557 10 Sep 2014
PDF 1036 10 Sep 2014
PDF 148 10 Sep 2014
PDF 83 10 Sep 2014
PDF 135 10 Sep 2014

Support & training

Search our extensive online knowledge base where millions of technical questions and answers are available 24/7.

Search answers from TI experts

Content is provided 'AS IS' by the respective TI and Community contributors and does not constitute TI specifications.
See terms of use.

If you have questions about quality, packaging, or ordering TI products visit our Support page.

Technical articles