Silicon N Channel MOSFET Tetrode BF 998 Features Short-channel transistor with high S/C quality factor For low-noise, gain-controlled input stages up to 1 GHz Type Marking Ordering Code (tape and reel) Pin Configuration 1 2 3 4 Package1) BF 998 MO Q62702-F1129 S SOT-143 D G2 G1 Maximum Ratings Parameter Symbol Values Unit Drain-source voltage VDS 12 V Drain current ID 30 mA Gate 1/gate 2 peak source current 10 Total power dissipation, TS < 76 C Ptot 200 Storage temperature range Tstg - 55 ... + 150 C Channel temperature Tch 150 Rth JS < 370 IG1/2SM mW Thermal Resistance Junction - soldering point 1) K/W For detailed information see chapter Package Outlines. Semiconductor Group 1 04.96 BF 998 Electrical Characteristics at TA = 25 C, unless otherwise specified. Parameter Symbol Values Unit min. typ. max. DC Characteristics Drain-source breakdown voltage ID = 10 A, - VG1S = - VG2S = 4 V V(BR) DS 12 - - Gate 1-source breakdown voltage IG1S = 10 mA, VG2S = VDS = 0 V(BR) G1SS 8 - 12 Gate 2-source breakdown voltage IG2S = 10 mA, VG1S = VDS = 0 V(BR) G2SS 8 - 12 Gate 1-source leakage current VG1S = 5 V, VG2S = VDS = 0 IG1SS - - 50 Gate 2-source leakage current VG2S = 5 V, VG1S = VDS = 0 IG2SS - - 50 Drain current VDS = 8 V, VG1S = 0, VG2S = 4 V IDSS 2 - 18 mA Gate 1-source pinch-off voltage VDS = 8 V, VG2S = 4 V, ID = 20 A - VG1S(p) - - 2.5 V Gate 2-source pinch-off voltage VDS = 8 V, VG1S = 0, ID = 20 A - VG2S(p) - - 2 Semiconductor Group 2 V nA BF 998 Electrical Characteristics at TA = 25 C, unless otherwise specified. Parameter Values Symbol Unit min. typ. max. AC Characteristics Forward transconductance VDS = 8 V, ID = 10 mA, VG2S = 4 V f = 1 kHz gfs - 24 - mS Gate 1 input capacitance VDS = 8 V, ID = 10 mA, VG2S = 4 V f = 1 MHz Cg1ss - 2.1 2.5 pF Gate 2 input capacitance VDS = 8 V, ID = 10 mA, VG2S = 4 V f = 1 MHz Cg2ss - 1.2 - Reverse transfer capacitance VDS = 8 V, ID = 10 mA, VG2S = 4 V f = 1 MHz Cdg1 - 25 - fF Output capacitance VDS = 8 V, ID = 10 mA, VG2S = 4 V f = 1 MHz Cdss - 1.05 - pF Power gain (test circuit 1) VDS = 8 V, ID = 10 mA, f = 200 MHz, GG = 2 mS, GL = 0.5 mS, VG2S = 4 V Gps - 28 - dB Power gain (test circuit 2) VDS = 8 V, ID = 10 mA, f = 800 MHz, GG = 3.3 mS, GL = 1 mS, VG2S = 4 V Gps - 20 - Noise figure (test circuit 1) VDS = 8 V, ID = 10 mA, f = 200 MHz, GG = 2 mS, GL = 0.5 mS, VG2S = 4 V F - 0.6 - Noise figure (test circuit 2) VDS = 8 V, ID = 10 mA, f = 800 MHz, GG = 3.3 mS, GL = 1 mS, VG2S = 4 V F - 1 - Control range (test circuit 2) VDS = 8 V, VG2S = 4 ... - 2 V f = 800 MHz Gps 40 - - Semiconductor Group 3 dB BF 998 Total power dissipation Ptot = f (TA) Output characteristics ID = f (VDS) VG2S = 4 V Gate 1 forward transconductance gfs1 = f (VG1S) VDS = 8 V, IDSS = 10 mA, f = 1 kHz Gate 1 forward transconductance gfs1 = f (VG2S) VDS = 8 V, IDSS = 10 mA, f = 1 kHz Semiconductor Group 4 BF 998 Gate 1 forward transconductance gfs1 = f (ID) VDS = 8 V, IDSS = 10 mA, f = 1 kHz Gate 1 input capacitance Cg1ss = f (VG1S) VG2S = 4 V, VDS = 8 V, IDSS = 10 mA, f = 1 MHz Gate 2 input capacitance C g2ss = f (VG2S) VG1S = 0 V, VDS = 8 V IDSS = 10 mA, f = 1 MHz Output capacitance Cdss = f (VDS) VG1S = 0 V, VG2S = 4 V IDSS = 10 mA, f = 1 MHz Semiconductor Group 5 BF 998 Drain current ID = f (VG1S) VDS = 8 V Power gain Gps = f (VG2S) VDS = 8 V, VG1S = 0, IDSS = 10 mA, f = 200 MHz (see test circuit 1) Noise figure F = f (VG2S) VDS = 8 V, VG1S = 0, IDSS = 10 mA, f = 200 MHz (see test circuit 1) Power gain Gps = f (VG2S) VDS = 8 V, VG1S = 0, IDSS = 10 mA, f= 800 MHz (see test circuit 2) Semiconductor Group 6 BF 998 Noise figure F = f (VG2S) VDS = 8 V, VG1S = 0, IDSS = 10 mA, f = 800 MHz (see test circuit 2) Gate 1 input admittance y11s VDS = 8 V, VG2S = 4 V, VG1S = 0, IDSS = 10 mA (common-source) Gate 1 forward transfer admittance y 21s VDS = 8 V, VG2S = 4 V, VG1S = 0 IDSS = 10 mA (common-source) Output admittance y 22s VDS = 8 V, VG2S = 4 V, VG1S = 0 IDSS = 10 mA (common-source) Semiconductor Group 7 BF 998 Test circuit 1 for power gain and noise figure f = 200 MHz, GG = 2 mS, GL = 0.5 mS Test circuit 2 for power gain and noise figure f = 800 MHz, GG = 3.3 mS, GL = 1 mS Semiconductor Group 8