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UC1825B-SP: Need to create a SPACE Power supply - Grade LLC Controller 500W. I'm stuck between a UC1825B-SP and UC1875-SP.

Part Number: UC1825B-SP
Other Parts Discussed in Thread: UC1875-SP, , PMP9622, UCC3895

Hello TI Power Designers,

I have a question concerning a possible TI solution for a LLC Resonant power Controller (SPACE grade solutions). I have been searching and reviewing several devices and wish to get some feedback on what I found.

To start, I'm looking to design a very small power module, as small as I can possibly get it.

I find a two devices, the UC1825B-SP, and the UC1875-SP. The first is not a LLC Resonant Controllers, the second is a resonant solution that I am pursuing.

I have already downloaded the TINA simulation file for the UC1825B-SP and it simulated fine.

Next, I'm trying to simulate the UC1875-SP, I don't think this is available for a TINA Transient simulation. I do know that a SPICE model exist for the UC1875-SP, but I have not located it yet.

I think I'm going to go with the UC1875-SP device for the Resonant ZVS Phase Shift Design. My first question, is there a design download for TINA, or do I have to download TI PSPICE?

I did locate many papers on the TI Website, showing Phase Shift ZVT 500W, 40W/in^3 paper dated 1993. 

Thanks for the help.

Thomas L Flack




  • Hello Thomas,

    I am surprised to hear a want for an LLC converter space solution, if only because variable frequency converters are generally considered nightmares for worst case analysis.

    We don't have controller solutions that support LLC's because of the above issue.

    As far as the UC1875-SP, we don't have an available PSPICE model nor do we have an example circuit.



  • Hi Daniel,

    I'm did a little research within the TI offerings and noted that TI has a Phase Shift Evaluation board PMP9622, based on the UCC3895 (350 Watt). My thought, I can use this board to get started on a design, enough where I can substitute the UC1875-SP, therefore giving the project SPACE level I require.

    By the way, this  PMP9622 eval board comes with all the design support items, except one thing, no Transient Simulation model. There is a UCC3895 available, but it is totally different from the eval board. It actually goes with an older eval board, SLUS1570 EVM SLUU109A (2011)

    Can you point me in the direction where I can get a TINA Transient simulation for this latest eval board that is now available for PMP9622. If not available, I will have to manually CUT-PASTE the components from the (paper schematic) of the real 350 Watt Power Supply Eval Phase-Shift.

    Thanks for the great help.

    Thomas L Flack



  • Hey Thomas,

    Our PMP evaluation boards generally do not provide transient models. I am unable to find or give you a transient model for the evaluation board.