Tool/software:
Hi,
We’ve designed a board intended to harvest energy from a current transformer and use it to charge a supercapacitor. In addition to energy harvesting, the system measures the current produced by the CT and transmits the data wirelessly. The system becomes operational once Vsupercap reaches 1.8V.
The issue we’re experiencing is that once Vsupercap exceeds 3.3V, the output of the TPS631000 doesn’t remain stable at 3.3V but starts to rise.
In our tests, for example, when Vsupercap reaches 4.0V, Vout rises to 3.8V.
Below is the schematic:
The load consumption is at around 200uA @3.3V. We have tried both PFM and forced PWM mode but the issue remains in both cases.
Do you have any idea why this is happening? And what would you suggest as a solution?
Best,
