You can use an npn or a pnp bjt in a common emitter amplifier circuit. The decision of which one to use is based on whether you want the collector and base to be more positive (npn) or more negative (pnp) than the emitter.
output current is zero
Much lower. Check out electronics sites to get the formulae for each.
The emitter bypass capacitor in a common emitter amplifier will have less resistance as the frequency increases. Since gain in this configuration is collector resistance divided by emitter resistance (within limits of hFe), the gain will thus increase for higher frequencies, making this into a high pass filter.
An amplifier amplifies voltage or current. The most basic amplifier consists of a transistor where a signal is fed into the base and is output to the emitter or collector. For simple, low frequency applications (not RF), it may be simpler to use an operational amplifier (op amp) than designing your own amplifier. Also, the data sheets provide very helpful schematics for creating an amplifier. A very common one is the 741; these are also fairly cheap.
This is a particular transistor amplifier configuration. In general, the input signal is applied to the base, the collector is connected to a supply voltage, and the output is taken between the emitter and power supply common. One of the characteristics of the emitter follower is the output voltage "follows" the input, but the output is reduced by the Vbe voltage (the voltage drop between base and emitter, approximately 0.7 V for a silicon bipolar transistor).
With a common emitter amplifier it's the emitter that is usually grounded.
Common Emitter - Class A Amplifier.
No the base emitter circuit is not the same as a common base circuit. The three BJT circuits all have the base emitter circuit. Wheter each terminal is common to both inputs and outputs of the circuit determines the type of transistor configuration.Henry Lee Everson PE;229-560-9769
In electronics, a common-emitter amplifier is one of three basic single-stage bipolar-junction-transistor (BJT) amplifier topologies, typically used as a voltage amplifier. In this circuit the base terminal of the transistor serves as the input, the collector is the output, and the emitter is common to both (for example, it may be tied to ground reference or a power supply rail), hence its name.
bbc
output current is zero
Gain, in the common emitter amplifier, is beta (hFe) or collector resistance divided by emitter resistance, whichever is less. Substituting a different beta (hFe) transistor will affect gain, if hFe is less, or increase stability and design margin, if hFe is greater.
I think you mean a common emitter amplifier, which is an amplifier of voltage. Emitter-follower or common collector amplifiers are used to match impedances, or to amplify power or current. The emitter-follower is a type of common emitter circuit that has a resistor between the emitter and ground. The output signal is taken from the point between the emitter and its resistor.
In an NPN transistor an emiter follower refers to an amplifier topology. The emiter follower configuration is when the emitter of a N-Type Bipolar Junction Transistor (BJT) is connected to the common point on a circuit (typically ground). This is not always the case, however, because many amplifier configuration exist.
cascade: the output of one amplifier stage is connected to the input of another amplifier stages, it's also connected in series. cascode: it said to be cascode, when it has one transistor on the top of another where a common emitter transistor drives a common base transistor.
Much lower. Check out electronics sites to get the formulae for each.
Common base transistor if the emitter is open current Ie=0 but a small collector current thus exist.this current is reversed biased collector to the base voltage it is represented by Icbo while common emitter is d base terminal is open circuit and the base junction is reversed biased current Icbo flow from the tcollector to the emitter in the external circuit this current is called leakage current.