So if you looking for a PNP transistor that could switch high voltage loads within 0.2A then this 2N3906 transistor might be the right choice for you. This transistor has only a gain value of 300, hence not suitable for amplifier circuits. It very much similar to the bc557 transistor except for that it has high collector to emitter voltage and hence high voltage loads can be toggled. The 2N3906 is a commonly used PNP transistor. When base current is removed the transistor becomes fully off, this stage is called as the Cut-off Region and the Base Emitter voltage could be around 5V. This stage is called Saturation Region and the typical voltage allowed across the Collector-Emitter (VCE) or Base-Emitter (VBE) could be 40 and 5 V respectively. When this transistor is fully biased then it can allow a maximum of 200mA to flow across the collector and emitter. To bias a transistor we have to supply current to base pin, this current (IB) should be limited to 5mA. The maximum amount of current that could flow through the Collector pin is 200mA, hence we cannot connect loads that consume more than 200mA using this transistor.

This is where a PNP transistor differs from a NPN transistor, a Logic state (blue colour) is used to toggle between Ground and Signal Voltage (Emitter-Base Voltage VBE) as shown belowĢN3906 has a gain value of 110 to 300, this value determines the amplification capacity of the transistor. Note: Complete Technical Details can be found at the 2N3906 datasheet given at the end of this page.īC157, BC558, 2SA1943, BD140, S8550, TIP127, TIP42ĢN3906 is a PNP transistor hence the collector and emitter will be closed (Forward biased) when the base pin is held at ground and will be opened (Reverse biased) when a signal is provided to base pin.

Continuous Collector current (IC) is 200mA.

2n3906 transistor substitute for 2n1307