18Vdc-36Vdc Input, 28V/100W Active Clamp Forward Reference Design
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This reference design uses the UCC2897A active clamp controller to generate an isolated 28V/3.6A output from a standard 24Vdc telecom input. This design uses diode rectification on the output stage and achieves efficiencies up to 93%. The output is adjustable down to 24V by changing a single resistor value.

  • 18-36V Input, 28V/3.6A Output
  • Standard 24Vdc telecom input range
  • Efficiency up to 93%
  • Diode Rectification
  • Adjustable Output as low as 24V
  • Active Clamp Forward Topology, featuring UCC2897A Controller

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Schematic/Block Diagram

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Design Files

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(Output Voltage 1)
Vin (Min) (V)18
Vin (Max) (V)36
Vout (Nom) (V)28
Iout (Max) (A)3.6
Output Power (W)100.8
Input TypeDC
TopologyForward- Active Clamp

TI Devices (1)

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Part Number Name Product Family Sample & Buy 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)
UCC2897A Download Download
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Technical documentation

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User guide (1)
Title Type Size (KB) Date
PDF 2242 10 Feb 2012
Design files (4)
Title Type Size (KB) Date
ZIP 328 10 Feb 2012
PDF 133 10 Feb 2012
PDF 22 10 Feb 2012
PDF 45 10 Feb 2012

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