3SK238 Silicon N–Channel Dual Gate MOSFET Application CMPAK-4 UHF RF amplifier Features 2 • Excellent cross modulation characteristics • Capable of low voltage operation 3 1 4 1. Source 2. Gate1 3. Gate2 4. Drain Table 1 Absolute Maximum Ratings (Ta = 25°C) Item Symbol Ratings Unit ——————————————————————————————————————————— Drain to source voltage VDS 12 V ——————————————————————————————————————————— Gate1 to source voltage VG1S ±10 V ——————————————————————————————————————————— Gate2 to source voltage VG2S ±10 V ——————————————————————————————————————————— Drain current ID 35 mA ——————————————————————————————————————————— Channel power dissipation Pch 100 mW ——————————————————————————————————————————— Channel temperature Tch 125 °C ——————————————————————————————————————————— Storage temperature Tstg –55 to +125 °C ——————————————————————————————————————————— Marking is “XW–”. 3SK238 Table 2 Electrical Characteristics (Ta = 25°C) Item Symbol Min Typ Max Unit Test conditions ——————————————————————————————————————————— Drain to source breakdown voltage V(BR)DSX 12 — — V ID = 200 µA, VG1S = –5 V, VG2S = –5 V ——————————————————————————————————————————— Gate1 to source breakdown voltage V(BR)G1SS ±10 — — V IG1 = ±10 µA, VG2S = VDS = 0 ——————————————————————————————————————————— Gate2 to source breakdown voltage V(BR)G2SS ±10 — — V IG2 = ±10 µA, VG1S = VDS = 0 ——————————————————————————————————————————— Gate1 leakage current IG1SS — — ±100 nA VG1S = ±8 V, VG2S = VDS = 0 ——————————————————————————————————————————— Gate2 leakage current IG2SS — — ±100 nA VG2S = ±8 V, VG1S = VDS = 0 ——————————————————————————————————————————— Drain current IDSS 0 — 2 mA VDS = 6 V, VG1S = 0, VG2S = 3 V ——————————————————————————————————————————— Gate1 to source cutoff voltage VG1S(off) –0.7 — +0.7 V VDS = 10 V, VG2S = 3V, ID = 100 µA ——————————————————————————————————————————— Gate2 to source cutoff voltage VG2S(off) –0.1 — +0.8 V VDS = 10 V, VG1S = 3V, ID = 100 µA ——————————————————————————————————————————— Forward transfer admittance |yfs| 14 — — mS VDS = 6V, VG2S = 3 V, ID = 10 mA, f = 1 kHz ——————————————————————————————————————————— Input capacitance Ciss 0.9 1.25 1.8 pF —————————————————————————————— Output capacitance Coss 0.4 0.7 1.2 pF VDS = 6 V, VG2S = 3 V,ID = 10 mA, f = 1 MHz —————————————————————————————— Reverse transfer capacitance Crss — 0.015 0.03 pF ——————————————————————————————————————————— Power gain PG 16 19.4 — dB —————————————————————————————— Noise figure NF — 2.8 4 VDS = 4 V, VG2S = 3 V, ID = 10 mA, f = 900 MHz dB ——————————————————————————————————————————— 3SK238 Typical output characteristics Maximum channel power dissipation curve Pch (mW) 20 I D (mA) 200 50 1.2 V 12 1.0 V 8 0.8 V 0.6 V 4 0.4 V VG1S = 0.2 V 0 0 50 100 150 200 Ambient Temperature Ta (°C) 2 4 6 Drain to Source Voltage 8 10 VDS (V) 20 20 12 VDS = 4 V 3V 2V 1.5 V 8 4 VDS = 4 V 2.5 V VG2S = 1 V 0 0 0.5 1 1.5 2 –0.5 Gate1 to Source Voltage VG1S (V) I D (mA) (mA) Drain current vs. gate2 to source voltage ID Drain current vs. Gate1 to source voltage 16 Drain Current 1.4 V 16 Drain Current 100 Drain Current Channel Power Dissipation 150 VG2S = 3 V 16 2V 1.5 V 12 1V 8 4 0 VG1S = 0.5 V 1 2 3 4 5 Gate2 to Source Voltage V G2S (V) 3SK238 Power gain vs. drain current 20 25 20 VG2S = 3 V 15 2.5 V 10 2V 1.5 V 5 0.4 0.8 1.2 1.6 2 Gate1 to Source Voltage VG1S (V) Noise figure vs. drain current 5 NF (dB) 16 12 8 4 1V 0 Noise Figure PG (dB) V DS = 6 V f = 1 kHz Power Gain Forward Transfer Admittance |y fs | (mS) Forward transfer admittance vs. gate1 to source voltage 4 V DS = 4 V VG2S = 3 V f = 900 MHz 3 2 1 0 4 8 12 16 Drain Current I D (mA) 20 0 VDS = 4 V VG2S = 3 V f = 900 MHz 4 8 12 16 Drain Current ID (mA) 20