2sk879.pdf datasheet:

2SK879 TOSHIBA Field Effect Transistor Silicon N Channel Junction Type 2SK879 General Purpose and Impedance Converter and Condenser Microphone Applications Unit: mm High breakdown voltage: VGDS = -50 V High input impedance: IGSS = -1.0 nA (max) (VGS = -30 V) Low noise: NF = 0.5dB (typ.) (RG = 100 k, f = 120 Hz) Small package Absolute Maximum Ratings (Ta = 25C) Characteristics Symbol Rating UnitGate-drain voltage VGDS -50 V Gate current IG 10 mADrain power dissipation PD 100 mWJunction temperature Tj 125 CStorage temperature range Tstg -55~125 CNote: Using continuously under heavy loads (e.g. the application of high temperature/current/voltage and the significant change in temperature, etc.) may cause this product to decrease in the reliability significantly even if the operating conditions (i.e. JEDEC operating t