This part is a kind of semiconductor called 79M12.

Function of this product has 1 Ampere Surface Mount Negative Three Terminal Voltage Regulators.

Manufacturers : Thinki Semiconductor

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Some of the text within the PDF file :

79M05/79M12 ® 79M05/79M12 Pb Free Plating Product Pb 1 Ampere Surface Mount Negative Three Terminal Voltage Regulators Features ● Output Voltage: -5 & -12V ● Output current up to 1A ● No external components required ● Internal thermal overload protection ● Internal short-circuit current limiting ● Output transistor safe-area compensation ● Output voltage offered in 4% tolerance DPAK/TO-252 Standard Application Circuit 79M05/79M12 A common ground is required between the input and the output voltages. The input voltage must remain typically 2.0V above the output voltage even during the low point on the Input ripple voltage. XX = these two digits of the type number indicate voltage. * = Cin is required if regulator is located an appreciable distance from power supply fi [ ... ]

79M12 PDF Datasheet Download