TPS560430: Can the Fixed Version be Used as Adjustable Version?

Heinz Hornung

Part Number: TPS560430

Dear Sir or Madam,

We would like to use the TPS560430 for a 5.1V output, but couldn't get hold on the adjustable version.

The 3.3V version works in principal, but oscillates. Input voltage is 13.2V. C403 is currently not populated. A value of 220pF did not improve the situation.

Is it possible to adjust the feedback so that the dc/dc converter is stable?

Thanks a lot and all the best,

Heinz

over 3 years ago

0 Gui He over 3 years ago

TI__Mastermind 28396 points

Hi Heinz

We do not recommend using fixed3.3V as adjustable version for volume production. Also, the 100uH inductor value is too large while the 1uF Cout is too small. You can use the Webench tool which you can find on ti.com to help design.

https://webench.ti.com/power-designer/switching-regulator/customize/66?VinMin=8&VinMax=36&O1V=5&O1I=0.6&base_pn=TPS560430X&AppType=None&Flavor=None&op_TA=30&origin=pf_panel&lang_chosen=en-US&optfactor=3&Topology=Buck&flavor=None&VoltageOption=None

Thank you.

0 Heinz Hornung over 3 years ago in reply to Gui He

Prodigy 30 points

Hi,

just reducing the inductance to 10uH solved the issue (see attached image.

Thanks a lot!

Heinz

Power management

Power management forum

TPS560430: Can the Fixed Version be Used as Adjustable Version?