This part is a kind of semiconductor called STK442-090.

Function of this product has Function class AB 2 channels AF power amplifier.

Manufacturers : Sanyo

Image and pinout :

Some of the text within the PDF file :

SPECIFICATIONS No. STK442-090 1. Case Outline 14Pins (See attached outline drawing) 2. Function class AB 2 channels AF power amplifier 3. Application 50W audio use 4. Maximum Ratings / Ta=25deg Item Power Supply Voltage 1 Power Supply Voltage 2 Thermal Resistance Junction Temperature Operating Substrate Temperature Storage Temperature Available Time for Load Short-circuit *4 Symbol Conditions Vcc max(1) No signal Vcc max(2) Signal ,R L=8ohm ,6ohm Theta j-c Per one power TR Tj max Tc max Tstg Vcc=+-35V,RL=6ohm,f=50Hz ts PO=50W,1ch drive 2000.04.18 TENTATIVE Ratings +-54 +-47 2.2 150 125 -30 to +125 0.3 Unit V V deg/W deg deg deg s 5. Operating Characteristics Tc=25deg,RL=6ohm(Non-inductive Load),Rg=600ohm,VG=30dB Conditions *2 Item Symbol V f Po THD MIN. (V) (Hz) (W) (%) Po1 +-35 20 t [ ... ]

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