UCC28C54: Spice model not working in Ltspice - Issue with RT/CT pin

Ahmad Hosseini

Part Number: UCC28C54

Tool/software:

Hello,

I made a simple test circuit for UCC28C54 using spice model on the product page, the simulation freezes when Vdd reaches about 6V. However, if I provide a sawtooth on RT/CT pin, simulation works as expected.

Has anyone seen this issue?

Thanks.

6 months ago

0 Jonathan Wong 6 months ago

TI__Genius 10865 points

Hello Ahmed,

Please expect a delay in our response.

Regards,

Jonathan Wong

0 Adhvaidh Aravind 6 months ago

TI__Expert 4920 points

Hi Ahmad,
We are really sorry about the delay in our response. I noticed that you haven't placed a bypass capacitor at VDD, and VREF pin.

Please make the changes and get back to us. If you still face issues, please share the screenshot of the circuit without the pulse generator.

Thank you.

Best,

Adhvaidh

0 Ahmad Hosseini 5 months ago in reply to Adhvaidh Aravind

Prodigy 20 points

Hello,

To clarify, this is not a breadboard or any physical hardware that I have built. It is in simulation only using spice model on product page and Ltspice.

Are you able to make test circuit in Ltspice and test it?

Thanks

0 Pratik Adibatla 5 months ago in reply to Ahmad Hosseini

TI__Expert 8568 points

Hi Ahmed,

We have moved from spice in TI and we don't support it anymore. We can help you with technical query, apologize for the inconvenience. For simulation tool related issue, please reach out to the LTspice help team.

Best,

Pratik A.

Power management

Power management forum

UCC28C54: Spice model not working in Ltspice - Issue with RT/CT pin