what are the applications of common collector and common base transistors???

Answer 1

The applications are becoming fewer and fewer because MOSFET transistors perform so much better for the same amount of money.

But, to answer your question, a common base amplifier circuit using a BJT is a high voltage gain amplifier that has a low impedance input and a high impedance output.
A common collector amplifier is usually close to unity voltage gain (a little less than one), but has high current gain. It has high input impedance, and low output impedance.

Answer 2

you may desire to locate out ..... [a million] what's the output impedance ( from sensor or different out point ) that connect with the enter of this CE amplifier ? [2] From the ordinary impedance, %. a suited biasing community to establish the operation element. [3] what's the output point you assume comes out from this CE. elect the top to top voltage point which you assume. Then elect a suited ability grant that has extreme adequate voltage to help the will of CE. [4] what's the present Ic you assume to fulfill the output wattage requirement ? [5] what's the output impedance you assume to feed the subsequent point, it somewhat is significant to be sure the fee of Rc. [6] Estimate the ease factor with the help of evaluate Vin and Vout. [7] From above suggestions, %. a suited transistor that meet your requirement. [8] Calculate ( estimate ) resistors fee on biasing community, Re , Rc. [9] upload bypass capacitor to Re as mandatory . [10] upload coupling capacitors previously Base and Collector as mandatory. [eleven] Hook them up and attempt, refine the resistors and capacitors fee until eventually totally meet the layout requirement.