- The BD136 is another PNP and NPN transistor in the BD13x series. This transistor is housed in a TO-126 package. It can handle or drive a maximum collector current of -1.5A and a maximum pulse current of 2A, but it requires a suitable heatsink to function properly.
- Because the BD136 is a PNP transistor, the collector and emitter are closed (forward-biased) when the base pin is held at the ground and open (reverse biased) when a signal is applied to the base pin. A PNP transistor differs from an NPN transistor in this regard.
- The base pin’s small input current is used to generate a large output current at the other two terminals. This procedure is used for amplification.
- BD136 is made up of three layers, one of which is n-doped and the other two of which are p-doped. Between the two p-doped layers is an n-doped layer.
- The base pin is represented by the n-layer, while the emitter and collector are represented by the other two layers.
- Though both electrons and holes are important in conductivity because this is a PNP transistor, the majority of carriers are holes, as opposed to an NPN transistor, where the majority of carriers are electrons.
- The base pin is the main terminal responsible for the entire transistor action in both cases. The base pin functions as a valve, regulating the number of holes in PNP transistors and electrons in NPN transistors.
- It is important to note that NPN transistors are preferred over PNP transistors for amplification purposes because electron mobility in NPN transistors is better and faster than hole mobility in PNP transistors.
- The pin diagram of the BD136 medium power PNP transistor is shown below.
|Pin No.||Pin Name||Description|
|1||Emitter||Current Drains out through emitter, normally connected to ground.|
|2||Collector||Current flows in through collector, normally connected to load.|
|3||Base||Controls the biasing of the transistor; used to turn the transistor ON or OFF.|
- The working principle of this PNP transistor is straightforward and similar to that of an NPN transistor. In addition, in an NPN transistor, the base pin is positive, whereas, in a PNP transistor, it is negative.
- When there is no current at the base side, the transistor is turned on and both the emitter and collector terminals are forward biased.
- When there is current at the base terminal, the transistor is turned off, resulting in reverse bias on both the collector and emitter sides.
- Remember that NPN transistors are preferred over PNP transistors for amplification because electron mobility is better and faster than hole mobility in the PNP transistor.
Applications of BD136 Transistor
- Collector Current (IC) Maximum: -5A.
- Collector-Emitter Voltage (VCE) Maximum: -45V.
- -45V is the maximum collector-base voltage (VCB).
- -5V is the maximum emitter-base voltage (VEBO).
- 5 Watt is the maximum collector dissipation (Pc).
- 190 MHz is the maximum transition frequency (fT).
- DC Current Gain (hFE) Minimum & Maximum: 25 – 250.
- Max Temperatures for storage and operation should range from -55 to +150 degrees Celsius.
- TO-126 is the package type.
- PNP is the transistor type.