This part is a kind of semiconductor called BA10339FV.

Function of this product has Ground Sense Comparator.

Manufacturers : Rohm

Image and pinout :

Some of the text within the PDF file :

Datasheet Ground Sense Comparator BA8391G BA10393F BA10339 Series BA2903 Series BA2901 Series General Description General purpose BA8391G/BA10393F/BA10339xx and high reliability BA2903xxxx/BA2901xxx integrate one, two or four independent high gain voltage comparator. Operating supply voltage range of BA8391G/BA1039 3F/BA2903xxxx/BA2901xxx is wide(2V to 36V). And can be used in a variety of applications because current consumption is small. BA2903Wxx is a low input offset voltage products.(2mV max) Features  Operable with a Single Power Supply  Wide Operating Supply Voltage  Standard Pin Assignments  Input and Output are Ground Sense Operated  Open Collector  Wide Temperature Range Application  General Use  Current Monitor  Battery Monitor  Multi vibrator Ke [ ... ]

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