TPS62742: Input Voltage range wrt output voltage and current

awais ehsan

Part Number: TPS62742

Hello,

I am using TPS62742 for a battery operated circuit. The battery is single cell lithium thionyl chloride rated at 3.65V. My output voltage is 3.3V with a maximum output current of 150mA.

Is 3.65V input voltage a safe range for such an application?
I am asking because, in the datasheet (typical application circuit), the input voltage range is 4 -- 5.5V for a 3.3V load. However, in several graphs and from the Webench application circuit, a delta of 350mV is permissible.

Please let me know if such a system would work or is prone to failure.

Please find attached my reference schematic.

Thanks PWR_Management.pdf

TPS62742DSSR

over 4 years ago

0 Dorian Brillet de Cande over 4 years ago

TI__Genius 14856 points

Hello,

Typical application circuits are meant to give a better understanding to the customer of how to use the part in a system.

Yes, you can use this part in these conditions. This part can also enter 100% mode when VIN (even below 3.65, around 3.55V) is close to your output voltage, VOUT=3.3V.
Please make sure you are following the Layout guidelines , topic 12 in the D/S.
Thank you very much!

Best Regards,
Dorian

0 Dorian Brillet de Cande over 4 years ago in reply to Dorian Brillet de Cande

TI__Genius 14856 points

Hello,

I haven't heard back from you. Do you have any further questions?
Did it help you solve your queries?
Thank you very much!

Best Regards,
Dorian

0 awais ehsan over 4 years ago in reply to Dorian Brillet de Cande

Prodigy 230 points

Hello,
Thanks
Please find attached the layout images that I did for this system and supply.
Please let me know if you find any ambiguity or improvement.

Thanks sig1.PDF top layer PS.PDF sig2.PDF 4505.bottom layer.PDF Composite.PDF

0 Dorian Brillet de Cande over 4 years ago in reply to awais ehsan

TI__Genius 14856 points

Hi,

For stability and noise reasons, I advise you to have CIN and COUT sharing the same GND close and linked to the IC GND pad.

I recommend you relate to the Layout example in the Datasheet topic 12.2, there you have a nice example of what I just mentionned.

Here also you can find a really useful App note stating what are the best Layout guidelines in general: slyt614

Thank you very much!

Best Regards,

Dorian

0 Dorian Brillet de Cande over 4 years ago in reply to Dorian Brillet de Cande

TI__Genius 14856 points

Hello,

I haven't heard back from you. Do you have any further questions?
Did it help you solve your queries?
Thank you very much!

Best Regards,
Dorian

Power management

Power management forum

TPS62742: Input Voltage range wrt output voltage and current