Dear Team,
Vin is 12V, EN pin is R1838 plus 3.3V, both are provided by DC source, the following conditions have been tested
1. After 12V on, the EN pin provides 3.3V, but no output
2. When the 12V & EN pin are on at the same time, there will be output, but if you have tried to keep on/off at the same time, it will sometimes fail to turn on.
3. When 12V & EN pin are on & output at the same time, turn 3.3V off and on again, but there is still no output
If the above reduces Vin from 12V to 11.5V, everything is normal
Battery shift: The voltage range provided by Battery is 10.8~13.6V.
In addition, I have measured OVP & UVLO voltage, and it seems that the protection is not triggered, but it is found that when Vin 12V is on, the voltage detected by UVLO is about 2V, but when the 3.3V of the EN pin comes in, the UVLO will drop to 1.8V.
BR
Kevin