TPS56921 WEBENCH Support?

Hi Chris,

This part is currently not supported by WEBENCH. Can you try TPS54821 instead? It has a slightly smaller current rating.

Best regards,

Chris,

I forgot to mention that TPS54821 is supported by WEBENCH: http://www.ti.com/product/tps54821&lpos=See_Also_Container&lid=Alternative_Devices#toolssoftware

Best regards,

Hi Nikhil,

The TPS54821 has a voltage reference of 0.6V, while the TPS56921 is 0.8V.

1) Would the voltage reference difference affect the compensation component calculations in WEBENCH?

I did notice the TPS54620 is similar to the TPS54821, but it's voltage reference matches the TPS56921.

2) As far as the compensation component values determined by WEBENCH, may I use the TPS54620 WEBENCH model for the TPS56921?

We are targeting 4A at a 3.3V VOUT (will not use the TPS56921 VID control feature). I picked the TPS56921 for it's increased thermal capability (HTSSOP) compared to the TPS54821/TPS54620 3.5mm x 3.5mm QFN.

Thank you,

Chris

Hi Chris,

TPS54620 is not a  drop in replacement for TPS56921 as the loop is different which will affect the compensation values. If you have a 4A application, having a 9A part may be on overkill (especially since you do not need the VID feature). I would recommend that instead of picking a part yourself, you enter your specifications into WEBENCH Designer.

Please see the following link for 4.5V-17V Input, 3.3VOUT@4A. You can change it to your specifications later: http://webench.ti.com/webench5/power/webench5.cgi?lang_chosen=en_US&VinMin=4.5&VinMax=17&O1V=3.3&O1I=4&op_TA=30. 

Based on the solutions that you get, you can then pick one that best suits your needs.  The visualizer page will not only list the solutions, but will also provide you important parameters like cost, size, efficiency, max temperature, etc.

Let me know if that helps.

Best regards,

Hi Nikhil,

We require a split power input rail (PVIN 3.3V-12V / VIN 5V) and prefer the HTSSOP package.  The TPS56921 is the only option available.

Do you have an estimate on when WEBENCH will support the TPS56921?

Thanks,
Chris

Nikhil,

Much appreciated!

Thank you,

Chris

Chris,

TPS56921 is not in WEBENCH Power Designer currently. You can choose an alternate device in WEBENCH. WEBENCH Power Designer will give you the calculated temperature too, which should help you choose the right device for your application. One device that may fit the bill is TPS54020, which is 10A device (and it is in WEBENCH).

You can also post your question on Non-Isolated DC/DC forum and device experts there might be able to recommend more devices.

Regards