This part is a kind of semiconductor called STK433-070-E.

Function of this product has 2-channel class AB audio power IC.

Manufacturers : Sanyo

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Some of the text within the PDF file :

Ordering number : EN*A1488 Thick-Film Hybrid IC STK433-070-E Overview 2-channel class AB audio power IC, 60W+60W The STK433-070-E is a hybrid IC designed to be used in 60W × 2ch class AB audio power amplifiers. Applications • Audio power amplifiers. Features • Pin-to-pin compatible outputs ranging from 30W to 60W. • Can be used to replace the STK433-100 series (80W to 150W/2ch)and STK433-200/-300 series (3-channel) due to its pin compatibility • Miniature package (47.0mm × 25.6mm × 9.0mm) • Output load impedance: RL = 6Ω to 4Ω supported • Allowable load shorted time: 0.3 second • Allows the use of predesigned applications for standby and mute circuits. Series Models STK433-030-E Output 1 (10%/1kHz) Output 2 (0.4%/20Hz to 20kHz) Max. rated VCC (quiescent) 30W×2 ch [ ... ]

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