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RICH DAD POOR DAD BOOK REVIEW

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  RICH  DAD  POOR  DAD  BOOK REVIEW This is amazing book.   • Explodes the myth that you need to earn a high income to become rich • Challenges the belief that your house is an asset • Shows parents why they can't rely on the school system to teach their kids about money • Defines once and for all an asset and a liability • Teaches you what to teach your kids about money for their future financial success It's been nearly 25 years since Robert Kiyosaki’s  Rich Dad Poor Dad  first made waves in the Personal Finance arena. It has since become the #1 Personal Finance book of all time... translated into dozens of languages and sold around the world. Rich Dad Poor Dad  is Robert's story of growing up with two dads — his real father and the father of his best friend, his rich dad — and the ways in which both men shaped his thoughts about money and investing. The book explodes the myth that you need to earn a high income to be rich and explains...
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What is Bipolar Junction Transister (BJT) ?

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What is Bipolar Junction Transistor ? 

Bipolar Junction Transistor

  • The transistor is three-layer semiconductor device consisting of either two 'n-type' and one 'p-type' layers of material or two 'p-type' and one 'n-type' layers of material.
  • The former is called as 'npn' , while latter is called as 'pnp' .
So, there are two types of BJT - 

  1. npn-transister
  2. pnp-transister

npn and pnp Transistor 












                                        In each transistor following points to be noted :- 
  1. There are two Junction, so transistor can be considered as two diode connected back to back.
  2. There are three terminals.
  3. The middle section is thinner than other.


Naming of the Transistor terminal 
  • Transistor has three section of dopped semiconductor.
  • The section one side is called "emitter" and the opposite side is called "collector" and the middle section is called "base" , as shown in above figure.

Emitter 
  • The section one side that supplies carriers is called "Emitter" .
  • Emitter is always forward biased with respect to base so it can supply carrier.
  • For "npn-transister" emitter supplies holes to its junction.
  • For "pnp-transister" emitter supplies electrons to its junction.

Collector 
  • The section on the other side that collect carriers is called "Collector" .
  • The collector is always reverse biased with respect to base.
  • For "npn-transister" collector receive holes to its junction. 
  •  For "pnp-transister" collector receive electrons to its junction.


Base
  • The middle section which forms two pn-junction between emitter and collector is called base.


Some important factors to be remembered:- 

  • The transistor has three region named emitter, base and collector. 
  • The base is much thinner than other region.
  • Emitter is heavily dopped so it can inject large amount of carriers into the base.
  • Base is lightly dopped so it can pass most of the carriers to the collector.
  • Collector is moderately dopped.
  • The Junction between emitter and base is called emitter-base junction (emitter diode) and junction between base and collector is called collector-base junction (collector diode).
  • The emitter diode is always forward biased and collector diode is reverse biased.
  • The resistance of emitter diode is very small and the resistance of collector diode is very high.

Transistor operating modes:-
  • Active mode
Base-Emitter junction is forward biased and base collector junction is reverse biased.
  • Saturation mode
Base-Emitter junction is forward biased and base collector junction is forward biased.
  • Cut-off mode 
Both junctions are reverse biased.


Transistor connections:-

Transistor can be connected in a circuit in following three ways:-
  1. Common base
  2. Common emitter 
  3. Common collector 


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