TPS54318: Is there any risk when EN>VIN?

Johnny Guo

Part Number: TPS54318

Hi, team,

My customer has one new design that EN pin voltage is higher than VIN pin.

Just need to check with you whether there will be any risk when EN>VIN? I see from block diagram that there is current flow path between VIN and EN.

Thanks.

Johnny

over 5 years ago

0 JohnTucker over 5 years ago

TI__Guru**** 191445 points

Johnny,

I cannot think of any issue it would cause. I will let you know if I find out otherwise.

0 JohnTucker over 5 years ago in reply to JohnTucker

TI__Guru**** 191445 points

Johnny,

We are going to double check this. It may take a day or so.

0 JohnTucker over 5 years ago in reply to JohnTucker

TI__Guru**** 191445 points

Johnny,

I have revised information. I would not take EN above 3.3 V. For some devices in this family 3.3 V is already in the Abs Max table for EN.

0 Johnny Guo over 5 years ago in reply to JohnTucker

TI__Expert 4910 points

John,

In TPS54318 datasheet, the abs. maximum for EN is 7V.

In customer's design, VIN=3.3V, EN=4.5V. Is there any risk?

Thanks.

Johnny

0 JohnTucker over 5 years ago in reply to Johnny Guo

TI__Guru**** 191445 points

Johnny,

There seems to be some conflicting information on this. I will investigate it further. Please bear in mind that this upcoming week is a holiday in the US. My response may be delayed.

0 Johnny Guo over 5 years ago in reply to JohnTucker

TI__Expert 4910 points

John,

Appreciate your feedback soon, customer is waiting for our result for new board building.

Thanks.

Johnny

0 JohnTucker over 5 years ago in reply to Johnny Guo

TI__Guru**** 191445 points

Johnny,

There is a lot of conflicting data. It will probably take some time to unravel it as many of the original persons are no longer available. My conservative advice it to not have EN above VIn. Use a resistor divider to decrease the voltage. I have to look into this for another customer as well. stay tuned in the next week or so.

0 JohnTucker over 5 years ago in reply to JohnTucker

TI__Guru**** 191445 points

Johnny,

The EN voltage should always be less than Vin.

Power management

Power management forum

TPS54318: Is there any risk when EN>VIN?