TPS62143 - connect SW pins together?

Thank you John for your quick response!

So, is my schematic good?! I want to put 12V, and get 5V/2A?

I only looked at your specific question about the SW pins...

Thank you!!

Hello,

I am using this component to get 5v from 12v to supply another board. If I put 5v directly to this board through USB, I get 5v in the other side, but the component after seems burned. Is it logical?!!

Thank you

Just connecting 5V on the output of the device does not damage it. It has been tested at that condition. There must be something else. Can you share more details about your experiment?

I create a board shield on Arduino mega 2560 witch takes 12v/15A as Input. It has some component like heater cartridge, fan, transistor. The arduino takes 5v from 12v with MC33269D-5.0, so not from TPS62143. The TPS62143  powered a "CubieBoard" wich need 5v and 2A max.

When I powered the Cubieboard with the USB, and remove the 12v. The Fan on my Board turns, and the arduino will on. And after that, when I put 12v, I never get 5v on TPS62143.

That's it!!

Please help!!

Should I put a radiator on it?!! Because I don't put anyhthing.!!

Please Help me!! I need to find a response quickly!!

In a typical design TPS62143 is dissipating its internally generated heat through the power pad on the bottom. This perfectly works if the device is assembled on a PCB with a suitable layout. A heatsink would not be required then. I did not find layout information in this post so I can not check that.

If I read your comments right in your setup the TPS62143 does not work after removing USB power. There is no output voltage and it gets hot. Did it ever work before connecting USB?

Thank you for your response!!

Yesterday, I put directly the power 12v into my board. The cubieboard was directly supplied from TPS62143 with 5v.

After moment, TPS62143 gives 0v on the output. For the layout, I think that I put the necessary Copper "4A"

Any idea?!!

The device has a thermal shutdown. If it gets too hot it turns off itself. It would recover automatically after cooling down. But all this only works reliably if the device is properly soldered on a PCB.

If the device is not recovering it has been damaged by anything you did during your experiment. To dig into that deeper I need more information. A good start would be reviewing the PCB layout.

Attached to this post, the part of PCB which contain the component.

Thank you.

Thanks. Although this layout does not match to the schematic you have posted above, it helps. I am afraid this layout needs some rework. For example the input loop for connecting the input capacitor to the device is very wide. It is the most critical part of the circuit and needs to be as tight as possible. The output loop is wide as well. I also do not see thermal vias in the power pad. They would be required to transfer the heat from the device into the PCB.

You can find guidance for reworking your design in the device datasheet (capacitor selection page 19, 20; thermal design page 23; and layout page 22, 23) or in the EVM documentation.