BC637 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 60 V
• Collector-Base Voltage, max: 60 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 0.5 A
• Collector Dissipation: 0.625 W
• DC Current Gain (h_fe): 40 to 160
• Transition Frequency, min: 200 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92

The BC637 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, collector, and base leads.
Here is an image showing the pin diagram of this transistor.The complementary PNP transistor to the BC637 is the BC638.You can replace the BC637 with the BC639, KSC1008C or KSC2331.