The voltage gain in CC configuration is always less than 1. The collector voltage, ( Vc ) must be greater and positive with respect to the emitter voltage, ( Ve ) to allow current to flow through the transistor between the collector-emitter junctions.The current gain in CC configuration is same as in CE configuration.The ratio of change in collector current (ΔI C) to the change in emitter current (ΔI E) when collector voltage V CB is kept constant, is called as Current amplification factor. In the CB configuration, the input current is the emitter current I E and the output current is the collector current I C. The collector voltage V CB is kept constant throughout this. When the emitter voltage is applied, as it is forward biased, the electrons from the negative terminal repel the emitter electrons and current flows through the emitter and base to the collector to contribute collector current. as opposed to the input circuit of a transistor ( where the base - emitter. The common base connection for both NPN and PNP transistors is as shown in the following figure.įor the sake of understanding, let us consider NPN transistor in CB configuration. mined, then the dependent variables, base voltage, and collector current. The name itself implies that the Base terminal is taken as common terminal for both input and output of the transistor. If the transistor chip is thought of as a large number of elements in parallel, some of these will have a lower base forward voltage. In every configuration, the emitter junction is forward biased and the collector junction is reverse biased. The three types of configurations are Common Base, Common Emitter and Common Collector configurations. Using these 3 terminals the transistor can be connected in a circuit with one terminal common to both input and output in three different possible configurations. A transistor is a semiconductor device, so the. We will discuss functions of these three terminals in the working of the transistor. The three terminals have specific names that are as follows:. Emitter Follower & Darlington AmplifierĪny transistor has three terminals, the emitter, the base, and the collector. The transistor formed in the former case will be NPN transistor and that formed in the latter case is PNP transistor.Transformer Coupled Class A Power Amplifier.Use higher supply voltage at collector.Ĭommon base is not so useful with single supply or in DC amplifiers. If collector is at 5V and base too, emitter voltage may be a little less than 4.3V, because there is not enough base current. With 5V CPUs, it is at either 5V or 0VĮmitter is connected to the load. With CPUs, collector is usually either 0V or supply voltage.Ĭollector is at some posive voltage, like supply.īase. It is connected to the load, and the load is connected to supply voltage. So I'll write here things which have helped me.Ĭollector can be anything. They are all correct and they all can be used. There are 3 ways to connect a transistor: common emitter, common collector and common base. There should not be always in "should be between". Ive seen one figure (see attached image). The load to be switched by an NPN should be between the collector and +ve power, the common emitter configuration. It appears that base-emitter voltage (Vbe) in transistor is always assumed as 0.6 V in circuit analysis. “TTL with a “totem-pole” output stage”] –transistor_logic] ]( –transistor_logic)[
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