This part is a kind of semiconductor called AP6209.

Function of this product has 250mA Low- Quiescent Current Linear Regulator.

Manufacturers : Anwell Semiconductor

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AP6209 Series Anwell Semiconductor Corp. 250mA Low- Quiescent Current Linear Regulator Features General Description  2.0µA Quiescent Current (Typ.) The AP6209 series is a positive voltage regulator with high accuracy output voltage and ultra-low  Operating Voltages Range：+1.8V to +6.0V quiescent current which is typically 2.0μA. The device is ideal for handheld communication  Output Voltages Range：+1.2V to +5.0V with equipments and battery powered applications 100mV Increment which require low quiescent current.  Maximum Output Current：250 mA  Low Dropout: 150 mV @ 100mA (VOUT≧2.0 V)  High Accuracy of Output Voltage ±2.0% : VOUT≧2.5 V ±50mV : VOUT≦2.5 V  High Ripple Rejection：60 dB  Output Current Limit Protection (350mA) The AP6209 cons [ ... ]

AP6209 PDF Datasheet Download