BC317 Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -45 V
• Collector-Base Voltage, max: -50 V
• Emitter-Base Voltage, max: -6 V
• Collector Current − Continuous, max: -0.15 A
• Collector Dissipation: 0.31 W
• DC Current Gain (h_fe): 110 to 800
• Noise Figure, max: 2 dB
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92

The BC317 is manufactured in a plastic TO-92 case. When looking at the flat side with the leads pointed downward, the three leads emerging from the transistor are, from left to right, the emitter, base, and collector leads.
Here is an image showing the pin diagram of this transistor.The BC317 transistor can have a current gain of 110 to 800. The gain of the BC317A will be in the range from 110 to 220, for the BC317B it will be in the range from 200 to 450, for the BC317C it will be in the range from 420 to 800.The complementary NPN transistor to the BC317 is the BC320.The BC857 (SOT-23), BC857W (SOT-323), BC860 (SOT-23) and BC860W (SOT-323) is the SMD version of the BC317 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the BC317 with the BC320, KSP55, KSP56, KTC9015, MPS751, MPS751G, MPSA55, MPSA55G, MPSA56, MPSA56G, MPSW55, MPSW55G, MPSW56 or MPSW56G.