2N3904 Pin Configuration:
|Collector-Emitter Voltage||VCEO||-40 V|
|Collector-Base Voltage||VCBO||-40 V|
|Emitter-Base Voltage||VEBO||-5 V|
|Collector Current Continuous||IC||-200 mA|
|Power Dissipation||PD||625 mW|
- Package Type: TO-92
- Transistor Type: PNP
- Max Collector Current(IC): 200mA
- Max Collector-Emitter Voltage (VCE): 40V
- Max Collector-Base Voltage (VCB): 40V
- Max Emitter-Base Voltage (VEBO): 5V
- Max Collector Dissipation (Pc): 625 miliWatt
- Max Transition Frequency (fT): 250 MHz
- Minimum & Maximum DC Current Gain (hFE): 100 – 300
- Max Storage & Operating temperature Should Be: -55 to +150 Centigrade
Note: Complete Technical Details can be found at the 2N3906 datasheet given at the end of this page.
2N3906 Equivalent NPN Transistors:
BC549, BC636, BC639, 2N2222 TO-92, 2N2222 TO-18, 2N2369, 2N3055, 2N3906, 2SC5200
Brief Description on 2N3906:
The 2N3906 is a commonly-used PNP bipolar junction transistor intended for general purpose low-power amplifying or switching applications.2N3906 is a widely used transistor. This is also a famous transistor among hobbyists and students because it has been used in wide variety of electronic hobby and educational projects. The transistor is manufactured to perform general purpose tasks in electronic circuits hence it can be used for any general purpose requirement in electronic circuits that fall in its max specification values. The max collector current of the transistor is 200mA therefore it can be used to drive any load which falls under 200mA or 0.2A. Moreover the max collector dissipation value, DC current gain value also makes it ideal to use in wide variety of simple audio frequency applications.
2N3906 as switch:
When a transistor is used as a switch it is operated in the Saturation and Cut-Off Region as explained above. As discussed a transistor will act as an Open switch during Forward Bias and as a closed switch during Reverse Bias, this biasing can be achieved by supplying the required amount of current to the base pin. As mentioned the biasing current should maximum of 5mA. Anything more than 5mA will kill the Transistor; hence a resistor is always added in series with base pin. The value of this resistor (RB) can be calculated using below formulae.
RB = VBE / IB
Where, the value of VBE should be 5V for 2N3904 and the Base current (IB depends on the Collector current (IC). The value of IB should not exceed mA.
2N3906 as Amplifier:
A Transistors acts as an Amplifier when operating in Active Region. It can amplify power, voltage and current at different configurations.
Some of the configurations used in amplifier circuits are
- Common emitter amplifier
- Common collector amplifier
- Common base amplifier
Of the above types common emitter type is the popular and mostly used configuration. When uses as an Amplifier the DC current gain of the Transistor can be calculated by using the below formulae
DC Current Gain = Collector Current (IC) / Base Current (IB)
- Driver Modules like Relay Driver, LED driver etc…
- Amplifier modules like Audio amplifiers, signal Amplifier etc…
- VCB and VBE is high hence can be used to control voltage loads up to 40V
- Commonly used in TV and other home appliances