Features :Bi-Polar PNP TransistorDC Current Gain (hFE) is 300 maximumContinuous Collector current (IC) is 100mAEmitter Base Voltage (VBE) is 6VBase Current(IB) is 5mA maximumTo-92 PackageBC557 Transistor UsesAs you know a transistor can be used in various applications. The two major use cases for the BC 557 transistor are as a switch or as an amplifier just like any other BJT transistor.BC557 Transistor as switchWhen 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 / IBWhere, the value of VBE should be 5V for BC557 and the Base current (IB depends on the Collector current (IC). The value of IB should not exceed mA.BC557 Transistor as AmplifierA Transistor 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 areCommon emitter amplifierCommon collector amplifierCommon base amplifierOf 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 formulaeDC Current Gain = Collector Current (IC) / Base Current (IB)Difference between BC557A , BC557B and BC557CThe major difference between these variants is that they offer different gain(hfe). While the BC557A variant offers the lowest gain of 110 to 200, the BC557B offers a gain of 200-450 and the BC557C gives the highest gain of 450-800.ApplicationsDriver Modules like Relay Driver, LED driver etc..Amplifier modules like Audio amplifiers, signal Amplifier etc..Darlington pair SKU: EAP-001263 Categories: Component, Electronic Parts, Transistor Tag: BC557
