This part is a kind of semiconductor called MAC97A6.
Function of this product has (MAC97 Series) Sensitive Gate Triacs Silicon Bidirectional Thyristors.
Manufacturers : ON Semiconductor
Image and pinout :
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MAC97 Series Preferred Device Sensitive Gate Triacs Silicon Bidirectional Thyristors Designed for use in solid state relays, MPU interface, TTL logic and any other light industrial or consumer application. Supplied in an inexpensive TO−92 package which is readily adaptable for use in automatic insertion equipment. Features http://onsemi.com • One−Piece, Injection−Molded Package • Blocking Voltage to 600 Volts • Sensitive Gate Triggering in Four Trigger Modes (Quadrants) for all • • possible Combinations of Trigger Sources, and especially for Circuits that Source Gate Drives All Diffused and Glassivated Junctions for Maximum Uniformity of Parameters and Reliability Pb−Free Packages are Available* TRIACS 0.8 AMPERE RMS 200 thru 600 VOLTS MT2 G MT1 [ ... ]