Dear experts,
I'm using TPS54286 to generate 5V and 3,3V supply from 12V input.
Output 1 is 3,3V, and output 2 is 5V. Out 2 is enabled by microcontroller, and out 1 is always on.
Now I want to disable the out 1(3,3V) in the same way as out 2 (at the moment using a jumper, but shall be replaced by a small circuit...), but out 1 doesn't fully shut down. I see a voltage of about 1.4V on the output, and I measure pulses on the SW1 pin which makes me think the chip is still active!?
I tried putting a small load (3k3 resistor) on output 1, but the output voltage remains constant. Also tried a second chip, but with the same result.
According to the datasheet it should be possible to have PVDDx applied, and both outputs disabled where the chip should enter a shutdown mode drawing acouple µA... SEQ is left floating for independant control of the outputs. Am I missing something here?
