Class 4 PoE PD, 12-V, 2.1-A active-clamp forward converter reference design


Design files


This reference design implements a Power over Ethernet (PoE) power device (PD) active clamp forward converter with 12-V and 2.1-A output. A TPS23734 PD, pulse width modulator (PWM) controller provides all the necessary functions to implement the PoE PD control and the PWM control for the active clamp forward converter. This design uses secondary side regulation (SSR) with an optocoupler feedback.

  • Combined PD and PWM controller
  • Secondary side regulation using optocoupler
  • Optional 48-V adapter input
  • Frequency dithering for improved electromagnetic interference (EMI)
Output voltage options PMP23278.1
Vin (Min) (V) 37
Vin (Max) (V) 57
Vout (Nom) (V) 12
Iout (Max) (A) 2.1
Output Power (W) 25.2
Isolated/Non-Isolated Isolated
Input Type DC
Topology Forward- Active Clamp
?? View video with transcript Video

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.

TIDT300.PDF (1823 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

TIDMAP0.ZIP (2783 K)

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

TIDCG88.ZIP (3196 K)

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

TIDMAO9.ZIP (4204 K)

PCB layer plot file used for generating PCB design layout


Includes TI products in the design and potential alternatives.


CSD19534Q5A100-V, N channel NexFET™ power MOSFET, single SON 5 mm x 6 mm, 15.1 mOhm

Data sheet: PDF | HTML
Powered devices

TPS23734IEEE 802.3bt type 3 class 1-4 PoE PD with high efficiency DC-DC control

Data sheet: PDF | HTML
Shunt voltage references

TL431LIAdjustable precision shunt regulator with optimized reference current (pin layout: KRA)

Data sheet: PDF | HTML

Technical documentation

No results found. Please clear your search and try again.
View all 1
Type Title Date
Test report Class 4 PoE PD Active Clamp Forward Converter (12 V, 2.1 A) Reference Design PDF | HTML Aug. 03, 2022

Support & training

TI E2E™ forums with technical support from TI engineers

View all forum topics

Content is provided "as is" by 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, see TI support. ​​​​​​​​