2SD439 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 18 V
• Collector-Base Voltage, max: 20 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 1.2 A
• Collector Dissipation: 8 W
• DC Current Gain (h_fe): 60 to 320
• Transition Frequency, min: 150 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-126

Here is an image showing the pin diagram of this transistor.The 2SD439 transistor can have a current gain of 60 to 320. The gain of the 2SD439-D will be in the range from 60 to 120, for the 2SD439-E it will be in the range from 100 to 200, for the 2SD439-F it will be in the range from 160 to 320.Sometimes the "2S" prefix is not marked on the package - the 2SD439 might only be marked "D439".The complementary PNP transistor to the 2SD439 is the 2SB559.You can replace the 2SD439 with the 2SC1162, 2SC1368, 2SD793, 2SD882, BD185, KSD882, KSH882 or MJE520.