This post explains for the regulator.
The Part Number is APL5607.
The function of this semiconductor is 600mA Linear Regulator for DC Fan Speed Control.
The package is SOP-8, TDFN3x3-8 Type.
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The APL5607, APL5607A is a low quiescent current and low dropout linear regulator which is designed to power a DC fan and deliver up to 600mA output current. The output voltage follows the 1.6 times of VSET voltage and typical dropout voltage is only 220mV (typical) at 600mA output current.
This is a type of voltage regulator integrated circuit (IC) that is designed to provide a stable and regulated output voltage with a maximum output current capacity of 600 milliamperes (mA). Linear regulators are commonly used in electronic circuits to maintain a constant voltage level despite variations in input voltage and load current.
· Low Dropout Voltage: 220mV (Typical) @ 600mA
· Low Quiescent Current: 140mA
· Output Voltage / VSET Voltage: 1.6 Times
· Stable with Low ESR Ceramic Capacitors
· Over-Temperature Protection
· Current-Limit Protection with Foldback Current
· Notebook Fan Driver
· PC Peripherals
· Battery-Powered System