SMD SOT23-5 Please help me identify component

Can I ask for help in identifying the following SMD component? Package is SOT23-5. Marking is bPCGD . Probably is voltage detector but I dont know his parameters. It is a component of mainboard IP camera YI YHS3017. I add photos of the mainboard and a diagram of this component that I was able to measure. Pinuot 3 is connected to a nearby coil, pinout 2 is ground, pinout 5 is voltage from power supply (5V). I`ve looked in many catalogs but it is probably a unique label of the manufacturer. I've been looking for this information for several days. I wonder what is means small letter "b" on the marking? Its means country of production? Or manufacturer designation? Thank for your help!