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Current consumption of the buffer is 25mA max, Vdrop = 6V- 5V = 1V, Ploss = 25mW worst case. No need for a big package to dissipate heat. Selected TLV76050DBZR AP7375-50SA-7 for cheap price and , small package and VDROP = 350mV @ IOUT = 100mA (Typ.).
3.3V LDO backup: TLV76033DBZR AP7375-33SA-7
Input Pulldown/Pullup Resistors
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