ISO3086T: LDO for the secondary side

Ryoma Ohashi

Part Number: ISO3086T
Other Parts Discussed in Thread: TPS7A24, LP2985A,

Hi team,

My customer is considering to use our device and has 1 question.

In the EVM, LP2985A-50DBVR is used as a power source for the secondary side. But if you look up the product folder for LP2985A, TPS7A24 is introduced as a next gen for this device.

Will TPS7A24 be the recommended LDO for ISO3086T? I guess LP2985A is used in the EVM since it was the best device at that time. But since it is a bit old device, I was wondering if we can use newer device which has better availability.

Regards,

Ohashi

over 2 years ago

0 Kenneth Arnold over 2 years ago

TI__Expert 8030 points

Hi Ohashi-san,

Thanks for reaching out.

I have notified the team responsible for these devices so that they can provide you with the latest LDO recommendation for this application.

Regards,

Kenneth

0 Stephen Ziel over 2 years ago in reply to Kenneth Arnold

TI__Mastermind 37145 points

Hey Kenneth,

It's a little hard to understand the input power supply requirements to the LDO from the ISO3086T datasheet. What voltage range do you expect here? The TPS7A24 can give you 18V input but perhaps you can live with LVIN LDO's?

Thanks,

Stephen

0 Ryoma Ohashi over 2 years ago in reply to Stephen Ziel

TI__Expert 5425 points

Hi Stephen

About the customer's use case, they are considering to use transformer and LDO jsut like the below figure in the datasheet.

Please assume that Vcc1 is 3.3V and Vcc2 is 5V. And they will use 1:2 X-FMR.

So, I guess MVIN-LDO might be the good option since there will be a possibility that the input for the LDO might goes near 7V.

Regards,

Ohashi

0 Stephen Ziel over 2 years ago in reply to Ryoma Ohashi

TI__Mastermind 37145 points

Hi Ohashi,

The TPS7A24 looks like a good fit here to me. I agree that this is a better LDO than the older LP2985A for this application.

Thanks,

Stephen

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ISO3086T: LDO for the secondary side