This part is a kind of semiconductor called 79L09ACD.

Function of this product has Three-Terminal Low Current Negative Voltage Regulators.

Manufacturers : ETC

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PLANETA The Linear IC's Three-Terminal Low Current Negative Voltage Regulators DESCRIPTION 79L00A Series The 79L00A Series of three terminal negative voltage regulators is available with several fixed output voltages making them useful in a wide range of applications. These regulators are inexpensive, vise-to-use devices suitable for a multitude of applications that require a regulated supply of up to 100 mA. These regulators feature internal current limiting and thermal shutdown making them remarkably rugged. No external components are required with the 79L00A devices in many applications. These devices offer a substantial performance advantage over the traditional zener diode-resistor combination, as output impedance and quiescent current are substantionally reduced. The voltages avail [ ... ]

79L09ACD PDF Datasheet Download