TPS63002: 5v isn't generated from inout range between 3 to 4.2V

Hello Virendra,

Which Zener diodes are you using on the output?
What happens if you remove the Zener diodes?

Hi,

Results are without Zener Diodes. 

Thanks & Regards,

Virendra

Hello Virendra,

Where did you connect the power pad on the bottom side of the IC?
Does the IC create the right output voltage with no load?
What is the input voltage on the IC when you add load?

Hello Virendra,

I haven’t heard back so I’m assuming you were able to resolve your issue. If not, just post a reply below (or create a new thread if the thread has locked due to time-out)

Hi Brigitte,

Thanks for your help.
Bottom pad is connected on PCB by thermal pad.
Yes, initially it generates correct output but after 60 seconds it started falling upto 1.6 V, even though no load is connected.
I am using single lithium ion battery ( fully charged- 4.1V). But in future we will connect 4 ( parrallel connected lithium ion batteries) as input.

Regards,

Virendra

Hello Virendra,

Please observe the input voltage on C27 and the output voltage on C28 with an oscilloscope during startup of the system as well until the output starts to drop.

The schematic looks ok, so please share the part number of the inductor and input and output capacitors as well as the layout.

Hi Virendra,

Did you resolve your problem? Please share the PCB layout and the inductor part number. It could be that the device overheats due to improperly sized inductor, or non-optimal PCB layout.

Best regards,
Milos