Hi Sir,
Will the IC be damaged if there is no power to the IC and -0.55V appears on the output pin?
The 2.8Vout only apply the power to ON-SEMI CMOS sensor device.
But the Vout drop phenomenon while the sensor get the ambient light. (no power on the LDO and CMOS sensor)
TPS7A2028 schematic:
Vout waveform: