We use TPS26623 VSON10. We have the following schematic:
RTN is not connected to GND. PowerPAD ist connected to GND.
A relais ist placed after the OUT Pin. After the relais ia a capacitor (22µF) and optocouplers.
When the Relais is switched on, and everything works fine, the signals look like this:
Yellow: FLT (Pullup to 3V3)
Green: Out Voltage TPS
Blue: Don't care
But sometimes when we switch the Relais, the TPS goes into fault state and never recovers (You have to switch the 24V in). Here's a picture of the signals:
Green: OutPut Voltage TPS
Can you please help me why the TPS is going to fault state and doesn't recover?
Why does it sometimes work and sometimes not? Where is the difference?
What have we made wrong?
Thank you for your help