LM3281: Is there a similar part in a SOT-23 package or non BGA package with the same current output?

Hi josh,

Thank you for posting to our forum. I will look into this for you. Please expect a response by 1/23/19.

Thanks,
Aaron

Josh,

I was not able to find anything in a SOT23 that would meet the same output voltage and current requirements. I did find a couple of devices in our portfolio that are not BGA which may suit your needs. Check out TPS62046 and also TPS62082. They have similar performance in a different package.

Thanks,
Aaron

Hi Aaron,

Thank you so much, TPS62082 (TPS62082DSG for 3.3V) look very promising.

Our current switcher, the LM3281, was optimized (according to the TI datasheet) for:

- powering noise sensitive wireless connectivity chipsets and RF Front end modules from a single Lithium-Ion cell

We were hoping that any replacement would also be appropriate for this application.

Our product:

- runs off a singe 3.7 Lipo (voltage range from 3.0 to 4.2V)

- max current requirements around 1 Amp (but usually 500 mA)

- MCU and other onboard devices require 3.3V

- We have a Bluetooth / WiFi chipset and chip antenna on the pcb (2.4GHz range)

Just want to make sure the switcher replacement will not interfere with our RF performance (the LM3281 worked great in this regard).

Is there anyway you can confirm the TPS62082 regulator will be appropriate for our application based on the specs I gave?

The reason why I ask is that I used the TI workbench power design tool that the PN on Digikey linked to and when we set voltage input to around 3.3V the tool said the regulator would not work.

Link: https://webench.ti.com/webench5/power/launch_wb.cgi?part=TPS62082&fromdisty=digikey

Again, thank you for your help!

Josh,

There is not anything that immediately jumps out that would be an issue. The output voltage is spec'd very similarly between both devices. The TPS62082 is marketed for battery powered portable devices as well. Working with RF devices can be tricky however. So it is hard to say with 100% certainty that this will drop smoothly into your system.

Thanks,
Aaron

Hi Aaron,
Thank you, what the about the issue regarding the online design tool TI supplies to verify the TPS62082 will work with our constraints?
webench.ti.com/.../launch_wb.cgi

I tried it and the tool said we could not use the TPS with a voltage input less that 3.5V.
We need to be able to have Vin be as low as 3V if possible.

-Josh

Josh,

I think webench is mistaken. The datasheet states the input voltage range to be 2.3V to 6V.

Hi Aaron,

Great, one last question.

In the TPS62082 Datasheet there is an application example but it only applies to the adjustable version of this part. We are going to purchase the TPS62082DSGT (3.3V Output) version which does not need resistor for voltage output selection.

There is no example for using the non adjustable version (though it seems like you probably just don't add resistors) and wanted to see if there was an app note for the non adjustable part before we add this part to our design.

Is there anything available?

Thank you