BC550 Transistor Pinout, Equivalent, Features

The BC550 Transistor is general purpose BJT transistor of BC547 series. The transistors in this series are commonly used for wide purpose applications in commercial devices and also in academic and hobby electronic projects. This Transistor can be used for both switching and amplification.  When used as a switch it can control load until 100mA. The max collector dissipation is 500mW and the maximum DC current gain value is 800mW so it can also be used as a preamplifier or signal amplifier. BC550  made in different (hFE) values which can be determined by the last alphabet used after the transistor number if the last alphabet is “A” the (hFE) value will be 110 – 220, if “B” the (hFE) value will be 200 – 450 and if “C” then the (hFE) value will be 420 – 800.

Pinout of BC550 Transistor

BC550 Transistor pinout

Features of BC550:

  • Type of Package – TO-92
  • Noise Figure – 1.2 dB
  • Collector Current: 0.1 A
  • Type of – NPN
  • Collector & Emitter Voltage: 45 volt
  • Collector the Base Voltage: 50 volt
  • Emitter the Base Voltage: 5 volt
  • Transition Frequency – 150 MHz
  • Collector Dissipation – 0.5 Watt
  • DC Current Gain (hfe) – 110 – 800
  • Operating and Storage Junction Temperature Range -65 to +150 °C

Complement of NPN transistor

The complement of BC550  transistor is: the BC560.

BC550 Equivalent:

The Alternate of BC550 are: BC847 BC850 (SOT-23), (SOT-23) BC847W (SOT-323),  and BC850W (SOT-323).

Replacement transistor for the BC550

The Replacement of BC550 are: BC546 or BC547

How We Can Use It: 

BC550 transistor can be used in type of general applications. If we use as a switch that we should drive load of 100mA. Which is enough current to drive  microcontrollers, LEDs, relays, ICS, power transistors portion of a circuit etc. The emitter-base voltage is only 5volt so it can also be used at the output of microcontroller to operate loads. On the other hand it can also be used as an amplifier for audio and other small signals. Furthermore, this transistor can also be used as a preamplifier or audio preamplifier for any small electronic signals.

Applications of BC550 Transistor:

  • Signal Amplification
  • Audio Preamplification
  • Switching Loads Under 100mA
  • Audio Amplification
  • Microcontrollers Output
  • Darlington Pairs

How to Safely Long Run in a Circuit:

To get long performance from Transistor BC550  it is recommended to not operate load more than 100 mA and 45 volts. Always use a suitable base resistor to procure required base current to the transistor.BC550 Transistor is also projected using the transistor in recommended the temperature that is more than -65 centigrade and below 150 centigrade.

BC550 vs 3904:

BC550 Datasheet: Click