This part is a kind of semiconductor called 2SK30ATM.
Function of this product has Silicon N Channel Junction Type Transistor.
Manufacturers : Toshiba Semiconductor
Image and pinout :
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2SK30ATM TOSHIBA Field Effect Transistor Silicon N Channel Junction Type 2SK30ATM Low Noise Pre-Amplifier, Tone Control Amplifier and DC-AC High Input Impedance Amplifier Circuit Applications Unit: mm • High breakdown voltage: VGDS = −50 V • High input impedance: IGSS = −1 nA (max) (VGS = −30 V) • Low noise: NF = 0.5 dB (typ.) (VDS = 15 V, VGS = 0, RG = 100 kΩ, f = 120 Hz) Absolute Maximum Ratings (Ta = 25°C) Characteristics Symbol Rating Unit Gate-drain voltage VGDS −50 V Gate current IG 10 mA Drain power dissipation PD 100 mW Junction temperature Tj 125 °C Storage temperature range Tstg −55~125 °C JEDEC TO-92 Note: Using continuously under heavy loads (e.g. the application of high temperature/current/voltage and the significant change in JEIT [ ... ]