TPS53313: TPS53313 output current issue

Hi Irfan,

The first thing which jumps out at me when reviewing this is the ferrite bead between AGND and GND. Can you try shorting this out?

Also part of the reason for the mismatch between WEBENCH and the reference design is that WEBENCH design looks to be for 1.2V output instead. Something may have not been updated correctly when you were modifying this design. When I create a design for 5V output and 600 kHz, the components match reasonably well.

Anthony

Hi Anthony,

Thanks for the quick response. AGND and GND are shorted using ferrite bead . So what's the reason to remove it as I have designed my circuit with this and it works well.

Also as I have removed 10k to gnd at mode/ss pin then it goes to skip mode and provide 5v, 3.5 A .

I am still in a doubt as I don't have used any capacitor for current limit threshold so according to the data sheet it must provide 6A current which is needed one but I am not getting it.

Please check my altium circuit and reply me how can I make 5V, 6A power from it or is it possible or not ??

Thanks
Irfan

Hi Irfan,

Generally for most parts a low impedance connection is needed between the AGND pin and the PGND pins so connecting them together using a ferrite bead may cause issues. It is possible the ferrite bead is causing a larger voltage difference between the AGND and PGND pins which could then cause the current limit to trip early.

Please try connecting AGND to GND with a thick wire, solder or 0 Ω resistor instead of the ferrite bead.

Anthony

Dear Anthony,

Thanks for the quick update as we have less time in design remains. Still I have attached here my design schematic so please check it and let me know how to make 5V, 6A current in my design.

Thanks,

IrfanPRO101-004B-R001.pdf

Hi Irfan,

Have you tried shorting FB7 with a short thick wire, solder or 0 Ω resistor? What were the results?

Thanks,

Anthony

Hi Irfan,

Just checking in to see what the results of shorting FB7 were. If this did not work, let me know and I can help provide other suggestions. Most likely I will need to review your PCB layout.

Thanks,
Anthony

Hi Anthony,

I have checked with ferrite bead shorting but its of no use as resulting current is the same as old around 3.5A max.

Let me know your suggestion now. If you want to review the layout then please share me your mail I'd .

Thanks,

Irfan