Other Parts Discussed in Thread: PMP9622, UCC3895, , UCC28950, UC3875
I am designing a Phase Shift Full-Bridge DC-DC Converter. My design needs to be SPACE qualified, so I will use the UC1875-SP. I referencing the "PMP9622A which uses the UCC3895, (350 watt eval board) (PMP9622) to start my design because this is the only PSFB device where TI offers a TINA Encrypted SPICE model. The biggest problem is there is no TINA SPICE reference design for the UC1875-SP. So I have to use the next best thing to build a simulation ref design, which is the UCC3895.
The other really sad thing is the UCC3895 Phase Shift Full Bridge reference design that TI does provide is not even a PSFB design; it is for some sort of "Direct Drive Motor application. The really ironic thing is, the PMP9622A design mentioned above, TI offered the board once, (can't get now), nevertheless TI never offered a TINA reference design. WHY?
Note, the PIN-OUT for the UCC3895 are not the same as the UC1875-SP, but it seems to be a good start. I will also have to enter the UCC3895 "PMP9622", PDF schematic into TINA, as the PMP9622, does not have a completed TINA reference design from TI. After I enter the PDF -Schematic into TINA, I will change the output from the initial 350 watts to 600 watts.
Next, I decided to use the "TI-Power Stage-Designer-Tool", and I selected a PSFB Transformer Topology, I then enter my parameters, the tool states it cannot complete my design. After careful investigation, I learned the tool is really not a "Power Stage Tool". The Power-Stage tool is basically a tool that targets the UCC28950, (slua560c.pdf), and the tool is targeting an AC-DC board and is expecting an input nominal voltage of 400VDC. My design is based off the PMP9622A, which has a 150VDC inout, so this tool is useless; not allowing my VIN to be 150VDC, which is what the UCC3895 (PMP9622) board wants.
The Power Stage Designer tool should allow data entry for the PMP9622 as well. Where do I go from here? I need help, to be able to enter the Eval Board PMP9622 (UCC3895) 350 watt design into a TI Simulation Tool.
What I really need, in a SUPER BAD way is the UC1875-SP TINA SPICE model. Yes, I know it DON'T exist. So, I'm going in circles with bits and pieces of designs trying to start a PSFB SPACE qualified design. If I even had a UC3875 TINA SPICE Model, I would be golden. The UC3875 is PIN compatible with the UC1875-SP, this would save me TONS of time.
I wonder why there is no model representing the UC1875-SP or UC3875; at the same time the UC1875-SP is a SPACE qualified part. It is listed in the latest TI SPACE Components Brochure.
I also downloaded the PSPICE-4-TI, hoping this will help me forward. This did not go well. I figure this new tool package would help me complete the PSFB transformer model. To learn, I started a simple design, a simple OPAMP inverter to learn the tool, the OPAMP would not simulate, the tool complained that it could not converge the design. I quickly went back to TINA.
Yes, I did review some TI case files for this non-convergence using PSPICE-4-TI, seems others are having the same problems. One again, I ran back to TINA.
So. my struggles continue
