Datasheet for the 2SK1058 transistor from Hitachi Semiconductor, a small PDF of about 40 KB. The 2SK prefix marks a Japanese-registered N-channel field effect transistor, and this part is widely known as a power MOSFET used in audio amplifier output stages. The document lists absolute maximum ratings, electrical characteristics, pinout and package outline, which a technician needs when checking a suspect device, confirming leg order or choosing a substitute with comparable voltage, current and gate characteristics.
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