Not able to operate buck-boost converter.

Thread Starter


Joined Jan 21, 2024

I am facing issue with TPS61240 as a buck-boost converter. I am using TP4056 to charge the battery and DW01 (and FS8205) to protect the battery by referring this blog.

Also, note that I want to operate the other module; due to this I am using this below shown circuit to high/low ENABLE pin of TPS61240. So, I can turn power ON/OFF by turning buck-boost converter ON/OFF.

Now, issue is ENABLE pin does turn high but it turns low again instantaneously. Output of the buck-boost converter shows greater than 5V or sometimes 6-7V and comes back to 0.1-0.2V slowly.

Everything else is working but this buck-boost converter. I have tested CD4011 is and it working too(without buck-boost converter connected). can DW01 is causing this issue? Note that, I am using 500mA resettable fuse in series with USB power supply which goes further into switching diodes.

I tried removing fuse and DW01 but it issue is same.

I am attaching schematic below. I appreciate any suggestion and help.

Thank you so much.

Figure 1: buck-boost converter and CD4011 IC (using CD4093 footprint just for schematic)


Figure 2: Battery protection section
Figure 3: Tp4056 and switching diodes