TPS548B28: Failed to create design with WEBENCH®︎ Designer for TPS548B28

diverger

Expert 1275 points

Part Number: TPS548B28
Other Parts Discussed in Thread: TPS54JB20

Hi,

I failed to create a design with WEBENCH for TPS548B28, the specifications are:

Vin: 6 to 9 V; Vout: 5V; Iout: 15A

It seems there are no inductor candidate for this design specifications.

Is it a bug or TPS548B28 can't handle these specifications?

Any help?

Thanks.

over 2 years ago

0 David_Daniels over 2 years ago

TI__Mastermind 23985 points

I was able to create a design. It worked for me. But as you state an inductor is not selected.

You can run a design using TPS54JB20 device, the internal reference is different so the feedback resistors values will be different from TPS548B28.

the tool returns the IHLP3232DZERR47M01 for the inductor.

https://webench.ti.com/power-designer/switching-regulator/customize/512?VinMin=6&VinMax=9&O1V=5&O1I=15&base_pn=TPS54JB20&AppType=None&Flavor=None&op_TA=30&origin=pf_panel&lang_chosen=en-US&optfactor=3&Topology=Buck&flavor=None&VoltageOption=None

0 diverger over 2 years ago in reply to David_Daniels

Expert 1275 points

Yes, it seems the differences between the two are the reference voltage, and the behavior under OC. But why the WEBENCH work well with JB20? However, if you can confirm the 8B28 can handle my design specs, then I will stick to 8B28 on my board but design it in WEBECH with JB20.

BTW: It throw errors when open the links in your answer.

+1 David_Daniels over 2 years ago in reply to diverger

TI__Mastermind 23985 points

Where ever the TPS54JB20 can work, the TPS548B28 will work. Just change the feedback resistors.

The TPS54JB20 and TPS548B28 are same base silicon but with different otp trims for the fault response and voltage reference.

The issue with webench as been forwarded the webench support team for the root cause and resolution.

Thanks for the reporting the issue.

Best

0 Praveen Badiger over 2 years ago

TI__Expert 8365 points

Hi Diverger/David,

The inductor is coming out to be custom on WEBENCH because the values of IDC limits (Minimum ,target and maximum) are defined as zero. We have fixed this issue and changes will be available on ti.com in next release cycle by end of this month. We will let you know once it is done.