What is an S8050 Transistor : Pin Configuration & Its Working

An NPN Epitaxial Si transistor-like S8050 is mainly used for switching and amplification purposes. So it is one of the most frequently used transistors in different circuit designs. This transistor has an outstanding maximum gain capacity like 400 however normal gain is approximately 110 so that it is applicable in amplifiers.

As the name suggests, this transistor includes three layers where the P-doped layer is encapsulated in between the two N-doped layers. Here, the base terminal is a P-doped layer whereas the other two terminals like emitter and collector are N-doped layers respectively. This article discusses an overview of an S8050 Transistor.

What is an S8050 Transistor?

S8050 is a high current & low voltage transistor where its collector current is 700 mA & collector-emitter voltage like VCE is 25 V. To work this transistor very safely, the base current of this transistor must be restricted to 5mA.

S8050 is an NPN Transistor with high current & low voltage capabilities. This transistor is a three-terminal component like emitter, base & collector which are used for external connection through different circuits. These three transistor terminals are dissimilar in doping concentration wherever emitter is extremely doped as compared to both the terminals like collector and base.

S8050 Transistor
S8050 Transistor

The base terminal in the transistor can be doped lightly whereas the collector terminal is doped moderately. In the transistor, the small current at one terminal is mainly used to control the huge current at the remaining terminals.

Generally, transistors are available in two types like UJT & BJT where the S8050 transistor comes under BJT (Bipolar Junction Transistor) category. So these transistors are available with two charge carriers like holes & electrons where the majority of charge carriers are electrons.


This transistor includes two PN junctions like EB and CB. Here EB junction is forward biased whereas the CB junction is reverse biased. For better performance of S8050 transistor, it must operate in forward bias condition otherwise

Pin Configuration

The pin configuration of the S8050 transistor & its symbol is shown below. This transistor includes three pins where each pin and its functionality are discussed below.

S8050 Transistor Pin Configuration
S8050 Transistor Pin Configuration
  • Emitter
  • Base
  • Collector

Pin1 (Emitter): The flow of current will drain out using this terminal

Pin2 (Base): Transistor biasing can be controlled through this terminal

Pin3 (Collector): The current supplies through this terminal

Features & Specifications

The features and specifications of the S8050 Transistor include the following.

  • The type of package is TO-92
  • The type of transistor is NPN (BJT)
  • Collector Current Max (IC) is 700mA/0.7A
  • Voltage from collector to the emitter (VCE) max is 20V
  • Voltage from collector to base (VCB) Max is 30V
  • Voltage from emitter to base (VBE) Max is 5V
  • Dissipation of Collector (Pc) Max is 1 Watt
  • Transition Frequency (fT) Max is 100 MHz
  • Gain of DC Current (hFE) Min 40 – 400
  • Operating temperature (Max) ranges from -65 to +150 C
  • High Current & Low Voltage Transistor
  • Small Signal Transistor
  • Max Power is 2W
  • Transfer Ratio of forwarding Current/hFE Value is120
  • The designator Type is S8050
  • Transition Frequency is 150 MHz
  • The material used for Transistor Si


In the S8050 NPN transistor, both the terminals like the emitter & collector will be reverse biased when the base pin is held at the ground and will be closed (Forward biased) when a signal is provided to the base pin. The max gain value of this transistor is 300 & this value will decide the capacity of amplification. If the amplification is high then it is used for amplification.

But, the gain value at collector current will be 110 and the max current supply throughout the Collector terminal is 700mA, so we cannot control different loads which operate by suing above 700mA through this transistor. A transistor can be biased once the current supply is provided to the base pin that must be restricted to 5mA.

Once this transistor is completely biased then it allows up to 700mA of current to supply across the emitter & collector terminals, so this phase is known as Saturation Region. The typical voltage used across the VCE or VCB could be 20V & 30V correspondingly. Once the current supply is removed at the base terminal of the transistor then it will be turned off, so this phase is called a cut-off region.

Alternatives S8050 transistors are 2N2369, 2N3904, 2N3055, MPSA42, BC547, S9014, 2N3906, SS8050, etc. Equivalent S8050 transistors are S9013 & 2N5830.

How to Protect an S8050 Transistor?

  • This transistor should operate below 20V to run safely within the circuits of electronic projects.
  • Similarly, the load in the circuit should operate under 0.7A/700mA.
  • An appropriate base resistor should be used to restrict the flow of current at the base terminal to its necessary level.
  • Do not expose it to heat above 150 C & under -60 C.

S8050 Transistor Circuit

The push-pull circuit using the S8050 transistor is shown below. In this circuit, the S8050 transistor plays a key role through a Class B amplifier. So its working is discussed below.

Generally, a Class B amplifier is also called a push-pull amplifier. It is one kind of multistage amplifier, frequently used in the amplification of audio within loudspeakers. The design of this circuit is very simple that needs two equal complementary transistors to work.

Push Pull Circuit Diagram
Push Pull Circuit Diagram

Here, complimentary is nothing but if we need an NPN transistor then its complimentary is PNP. Similarly, an S8050 is an NPN transistor so its complementary transistor will be the S8550 PNP transistor.

The S8050 transistor is a common NPN transistor and it is mainly used in the circuits for different general purposes like switch-based electronic circuits, audio amplification, etc.

Where to use S8050 Transistor?

The applications of the S8050 Transistor include the following.

  • The general purpose transistor-like S8050 is an ideal transistor, used to achieve general tasks within different electronic circuits. This transistor can be used as a switch within circuits that activates loads below 700mA.
  • Here, 700mA of current is sufficient to manage different kinds of loads like LEDs, relays, bulbs, etc. This transistor is also used as an amplifier within small amplification phases otherwise like a separate amplifier.
  • Class B Amplifiers
  • Low signal applications
  • Push-pull circuits
  • Switch for loads in the circuit
  • From low gain to high gain amplification
  • Audio Amplification Circuits
  • Use in circuits wherever high gain is necessary

Thus, this is all about an overview of the S8050 transistor datasheet which includes pin diagram, working, specifications, features, a circuit with working & its applications. This is a general-purpose transistor with a small signal, less voltage, and high current used to perform different tasks in electronic circuits. This kind of transistor is used as a switch to control loads under 700mA in different circuits. Here is a question for you, what are the disadvantages of the S8050 transistor?