11/22/2023 0 Comments Bc557 transistorThis transistor comes with three different versions BC550A,BC550B, and BC550C, if you are using this transistor as an amplifier make sure you check the gain of the transistor from the datasheet that can be found down below, because of different versions, the gain value differs which can completely ruin your calculations. The BC550 is a NPN Transistor, hence we need to provide a small amount of positive voltage to the base of the transistor to turn it on. When a positive voltage is applied to the base holes are created to the base so they start migrating to the emitter junction,this process thins out the depletion region from PN junction and more and more electrons start flowing to the and all of those electrons are collected by the collector. The BC550 Transistor is a general purpose N-P-N transistor, in which N-P-N transistor electrons work as the primary charge carriers that are emitted from the emitter of the transistor to the PN junction. Note: More technical information can be found in the BC550 datasheet, linked at the bottom of this page.īC547, BC548, BC549, 2n3904, 2SC5200,BC639, BC636, 2N222 TO-92, If you are designing a PCD or Perf board with this component then the following picture from the BC557 Datasheet will be useful to know its package type and dimensions.Electrons Emitted from Emitter Collected by the CollectorĮlectrons emitted from the emitter into the first PN junction Amplifier modules like Audio amplifiers, signal Amplifier etc.Driver Modules like Relay Driver, LED driver etc.When uses as an Amplifier the DC current gain of the Transistor can be calculated by using the below formulaeĭC Current Gain = Collector Current (I C) / Base Current (I B) Applications Of the above types common emitter type is the popular and mostly used configuration. Some of the configurations use in amplifier circuits are It can amplify power, voltage and current at different configurations. BC557 Transistor as AmplifierĪ Transistors acts as an Amplifier when operating in Active Region. Where, the value of V BE should be 5V for BC557 and the Base current (I B depends on the Collector current (I C). The value of this resistor (R B) can be calculate using below formulae. Anything more than 5mA will kill the Transistor hence a resistor is always added in series with base pin. As mentioned the biasing current should maximum of 5mA. As discussed a transistor will act as an Open switch during Forward Bias and as a Close switch during Reverse Bias, this biasing can be achieved by supplying the require amount of current to the base pin. When a transistor is use as a switch it is operate in the Saturation and Cut-Off Region as explain in above paragraph. Continuous Collector current (I C) is 100mA.When base current is remove the transistor becomes fully off, this stage is called as the Cut-off Region and the Base Emitter voltage could be around 660 mV. This stage is call Saturation Region and the typical voltage allowed across the Collector-Emitter (V CE) or Base-Emitter (V BE) could be 200 and 900 mV respectively. When this transistor is fully biase then it can allow a maximum of 100mA to flow across the collector and emitter. To bias a transistor we have to supply current to base pin, this current (I B) should be limited to 5mA. The maximum amount of current that could flow through the Collector pin is 100mA, hence we cannot connect loads that consume more than 100mA 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 V BE) as shown below:īC557 has a gain value of 110 to 800, this value determines the amplification capacity of the transistor. BC557 is a PNP transistor hence the collector and emitter will be close (Forward biase) when the base pin is hold at ground and will be open (Reverse biase) when a signal is provide to base pin.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |