Common-Base Configuration of a Transistor Neso Academy

Analog Electronics: Common Base Configuration of a Transistor
Topics Covered:
1. Different transistor configurations.
2. Common base configuration.
3. Common base configuration in active mode.
4. Nomenclature for voltage symbols.
5. Relation between emitter current, base current and collector current in active mode.
6. Common base current gain or amplification factor (α) .


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Best comment

1. sudipra biswas: i cant understand "recombination in base"..what is it means.......
2. Muhammad Rafiqul Islam Khan: Thank you for lecturing. I just want to know why npn or pnp symbol uses direction in > or out < sign ? What does the direction mean? Is it voltage direction? Or current ? Please , tell us.
3. yashitha Reddy: +Ritesh Choudhery sir I don't know anything about subject then how should I pass backlogs
4. Philangezwi Liwa: why is the emitter the input but current leaves through it
5. Asdf fdsa: Rajshekar Hiremath It's the leakage current from reverse biased of J2 when Emitter is open.
6. Chinmay Mohanty: The current goes from i/p to o/p right? then how here the current in moving into the i/p side?
7. Hasher khan: please upload power amplifier trasistor and its types class A, B AB C
8. Rafat Ashraf: what are the elaborated forms of VEE and VCC ?
9. Meghjit Mazumder: For,EB diode,one can neglect RE,since EB diode is in forward bias & any diode in forward-bias-condition has very low resistance.So,from that point of view,we can say,VBE=VEE. But,how can we say VCB=VCC because in that case,RC can't be neglected since the resistance in reverse-bias condition is very high.
10. TimeOfSmile -: nyc
11. Meet Vyas: I guess the left side will always be input and the right one will be output.
12. Neso Academy: It is not possible to upload power electronics lectures this year.
13. Ritesh Choudhery: Actually, Ie is due to Vee only. So Vee is the source. you cannot increase Ie without increasing Vee
14. Neso Academy: +karnati rameshwari Already explaind in the previous lectures. Try to watch all the lectures in proper sequence or you will get many doubts.
15. shubham aggarwal: at 9:15 you said Ib=(1-alpha)Ie ....so when we put dis value in Ie=Ic + Ib where Ic = (alpha)Ie + Ico....den it reduces to Ico =0 which is not possible
16. Barsha Pati: Sir value of alpha is 98% i.e. for value of emitter current to be 1 collector current is 0.98 so how is there a current gain
17. Jyothika Tammu: sir,how can u tell that alpha lies between 0.95-0.98?
18. Nida K: Plz derive the reverse saturation current Iceo and Icbo
19. ildisiri: ????
20. DINKER GAUTAM: why is base grounded
21. Aman Babbar: Arre great sir 😘 I become huge fan of your teaching😍😍🤗 Keep helping us tqsm...
22. Vaishnav PP: Sir i have a doubt of common base configuration. I need a solution. IB=50 MA And Ic=4 MA calculate Alfa. Plz sir you can
23. Nithya Anand: Why is J2 reverse biased in active region? And how do we know whether it needs to reverse biased or not?
24. Khaleel Shaik: nice
25. krishna meena: BUT in introdduction of bjt you write VEB WHY
26. HOW TO: Shubham Dhama u will gain voltage amplification..
27. Devavrat Somvanshi: it is reverse biased saturation current.
28. Parikshit Singh: Now I really feel to give all my tuition fees to NESO Academy !!! :D :D Thank you so much sir for your lectures.
29. gv bharadwaj: is a transistor is a 3 port device or a 2 port device??
30. Ashmita Prakash: Sir, why we neglect R while deriving any expression? Doesn't R has any significance?
31. Raza aslam: gud wirk
32. Rocking Balu: Pnp
33. Sandeep Verma: A lot of thank you ....................................sir
34. Mufakkir Hussain: What is Ib = (1-@)Ie..? Kindly explain
35. Germain Guerin: Hello Sir, just wondering why you call the source voltages Vee and Vcc... i understand the first e or c for emitter or collector but the second e and c for what?
36. Debjyoti Dey: try to include more solved examples along with.
37. vishal reddy: Sir why is alpha less than 1
38. lpavan Venkat: why is base grounded
39. Sree Charan Devarasetty: re model of common base configuration
40. Khaleel Shaik: For diploma EEE also sir
41. anubhav solanki: From where the equation at 7:00 come
42. Savitha Satish: Isn't CB amplifier applicable for only A.C?? But you used a D.C source.
43. ARVIND DHETARWAL: Sir, could it possible tht Vbe>Vee if we apply kvl in first loop thn Vee - Vbe + IeRe=0 and if we increase Ie thn Vbe>Vee
44. Ayush Verma: I am confused. Is common base configuration just a configuration or does it acts an amplifier? Because Ic=0.98xIe. So how can it act as an amplifier?
45. GAGANDEEP SINGH: Thank you
46. gautam p: thnxxx,, a lot its very help full
47. Manam VijayaChandra: To represent that only few of the electrons recombine in the base it is represented as IB=(1-alpha)IE
48. baby Supraja: sir, why the emittor is highly doped and base is lightly doped, if we do against this what will happen. you are saying out put is at collector but the collector current is into the diode. then how will we get the output
49. Neso Academy: We don't control and decide the advertisements on YouTube.
50. hasitha wijesinghe: wdf its not cerrrrrrrkit ... its circuit. your explain is so annoying man .you are repeating one thing so many times . though your theory is greatly explained
51. Rajshekar Hiremath: what is I cbo
52. Manam VijayaChandra: Emitter is heavily doped as it's job is to produce much number of electrons
53. Rameshwari venkatesham: Wt is recombination...I didn't get clarity...
54. youmna A: that means it doesn't amplify the current as alpha is nearly equal to 1, as far as i know
55. mamini pradhan: Neso Academy but why ...?? ...
56. Manam VijayaChandra: VBE is represented as VEE;VCB is represented as VCC for our convenience.....
57. NP Stock: Thank you for uploading videos with such clear explanations. It's a kind request to you sir that please upload practicals on electronics like digital gates using IC's.
58. Sushant Kesar: why we have taken re and rc
59. bhaskargowda km: Sir how we had base we get CBo
60. DHIVYA PA: Sir kindly make videos for control systems and electrical machines. Please help me sir
61. Ashok kumar patel: why arrow mark is on emitter always not on base or collector?
62. Mayuresh Mandal: These videos are excellent and very well made. Kudos to the creators!
63. aizen Uchiha: why emitter-base should be open to measure reverse saturation current in collector?? please help
64. rahul. garg: Sir E-B reverse biased hai toh input current Ib nahi hoga ? 🤔
65. C M: Oops damn lecture , excellent sir 😍😍😍😍😘😘😘😘😘😘😘😘😘😘😎
66. Shubham Dhama: at 1:43 instance in video you said we apply weak signal in input and get a amplified signal at output.......in common base current gain does not exceed 1 .....so how this is possible...
67. Burra Manikanta: sir, why is alpha 0.95 ....that point was not clear.
68. Aashiq s: Thank you Sir for the Lectures.Really helpful.
69. The Circle: If Ic/Ie is .98 then that means Ic is less than Ie. Then why do we say that there is a gain?
70. Bhavya Nandwani: why base terminal is grounded please explain
71. Tanvi Wadhwani: Sir I think there's one correction - proper nomenclature shld be V EB according to ur battery connection.. Pls check once
72. Sunil Rawat: sir can u make "logic family" lecture.
73. Diolindo Luis: you are the best at explaining sir
74. sudipra biswas: Thnq.......
75. Krishna Bakhu: thank you for lecture but sir why are you not provide alpha = negative sign ic devide by iE
76. Subrahmanya. Kulkarni: How did you derive Ic=alpha(Ie)
77. Samula Tarun venkatesh: Name the videos with no.s such that a series of lectures can b identified by the viewer
78. ANANDAN UMASANKAR: Why IB=(1-ALPHA)IE explain that formulae
79. TECH 25000V: plz prvide all leacture on power electronics sir for BE OR BTECH student
80. Other Guy: :)
81. Devavrat Somvanshi: because to operate transistor iin active mode, we have to connect o/p to reverse biased. that is done by connecting C to reverse biased voltage.
82. DEBABRATA ROY: sir please say what is leakage current?
83. kumar raja: How to take VBE and VCB voltage????
84. vithal kanakadandi: +Ali Azi can you share the link?
85. apurva gaygole: Dear sir all your lectures are very good. I am also a lecturer and wishing to make video lectures. Will you please tell me on which platform you created your lectures.
86. unknown LOL: tq sir!very well explained,ill have my exam on basic electronic,staying up to watch ur videos and understand all the concept, T.T
87. Simran Gadkari: Passing my ECCF exams only because of you, sir! Thanks a lot :)
88. GYAN PRAKASH: What are the significance(meaning) of the resistances Re and Rc ? If they r externally provided or internal properties of bjt? Please tell in detail.
89. Shivam Sarda: PLEASE DONT POP UP WITH THAT BITCOIN GUYS ADVERTISEMENT AGAIN, HE IS SO IRRITATING AND THAT ADVERTISEMENT IS SPAMMING MAN.
90. Shubham Shetty.k: What is recombination of base
91. KALYAN: Lpavan Venkat and the base is common for input and output
92. Ritesh Choudhery: Base is lightly doped so that there is less recombination in it and more charge carriers are able to pass to the collector region. The emitter is highly doped to get large number of charge carriers in forward bias.
93. Parikshit Singh: Using relation Ie = Ib + Ic put the value of Ic = alpha*Ie then Ib= Ie - Ic or Ib = (1-alpha)Ie
94. Apoorva G: How did we get base current as (1-alpha)of emitter current given at the ending of presentation When the base is grounded current should be zero ?
95. KALYAN: Lpavan Venkat because it common base transistor
96. Sr m: Thank you for these lectures... Very helpfull..
97. Puru Raj: See the previous lecture on working of transistors
98. nidhi moriya: sir its vry help
99. Laxmikant sharma: very important this videos thanx
100. Pro user: How do we determine which side is the input side or output side ?
101. shubham aggarwal: plzz correct me where I m wrong and explain me
102. Anant Goyal: First of all thank you so much sir for sharing knowledge with us. My doubt is why in the O/P characteristics of CE every curve ends at origin and why not in CB(it ends in 2nd quad in case of CB). THANK YOU
103. Niharika B: Thank you very much .........
104. Niaz Asif: Sir, how do i understand which is input or which is output of signal? Cause i saw it varies from emitter to base or collector... different input and output, but why? Can u please tell me or suggest me.thanks in advance
105. krypton blogs: Sir,at 5.15 you told Vcb =VCC if we neglect Rc ,but Rc have very large registance unlike Re ,so how can we neglect that?
106. kryptoknight: What is the Icbo current in the common base equation ?
107. wolf: thanks you Sir!
108. shantanu chavhan: sir but I don't understand Ie current bada kya Ic
109. sudipra biswas: & in this circuit diagram which is j1 and which is j2......?
110. ND BROTHERS: semester saver videos... thankyou sir..
111. Ketan Shahu: thank you sir
112. Shahid Mehmood: Sir value of Alpha is 98% i.e. for value of emitter current to be 1 collector current is 0.98 so how is there a current gain?
113. ganesh dilli: sir,wonderful lecture of ur's helped me in solving many doubts of transistor and pls..... upload working of low passand high pass filters also.......... thankyou for ur lecture
114. Kanchan Attri: Agar emitter base junction reverse bias hai to potential barrier greater hoga then how majority charge carriers pass this potential barrier???
115. Barsha Pati: satish vasamsetti I too have the same question. Appropriately this should be current loss
116. Manam VijayaChandra: It's simply the injection of electrons from emitter into holes of base😊😊
117. Aman Kumar: Thank u, twas really conceptual and eliminating out confusions. I liked the way, you drew Vcb and Vbe later in the circuit and gave understanding of its terminals. Most of the lectures i found previously, they seemed to mug up the circuit diagram without and explanations and then explain just the results, that too in a confusing way.
118. Gayathri Sudarsan: how does electrons combining with holes in the base region cause base current?
119. kuldeep muzahid Tiwari: How we decided that which is input and which is output side...???? please answered sir
120. Dima Saginbaev: Nice lecture! Thank you. I have a question though, the base current is denoted as (1-alpha)Ie, i.e due to the electrons recombined in the base, and the new holes needed to compensate this. But what about hole injection into the emitter, doesn't it affect the current, don't we need even more holes to compensate?
121. Apurva Dhokane: it was really helpful tq sir
122. KORADA DURGA PRASAD RAO: sir send the link in which you have explained the directions of current components
123. shantanu chavhan: thank you sir
124. bye: Can somebody please tell me why the terminal that attached to C was +ve even tho it is n type?
125. TECH 25000V: nice sir........i m happy becoz you created playlist for each subject........so continue sir it very helpful
126. Ali Azi: watch previous videos
127. The Prohibited Road: Thank you sir
128. benny talluri: Sir why we are using Re and Rc ?
129. jaya shri: Sir when electrons recombine with holes in base then which electrons contribute to I(BE) pls explain
130. Asdf fdsa: baby Supraja God knows haha
131. Ashmita Prakash: Ok sir, thank you.
132. Maryam Saeed: please explain how we can obtain voltage gain in common base?and why we call it as current buffer?
133. Vivek Kumar: TECH 25000V haha
134. xaffux: Sir why is alpha (gain) multiplied with IE ??To find IC I know but how?
135. ANAND SUBBURAJ: Sir what happen when Re and Rc resistors was not there
136. Cherukumudi Saisrividhya: Sir. We r fortunate to have ur lectures seriously... Thanks a lot. Sir y emitter should be highly doped as well as base is lightly.? What's d reason behind it. Plz tell me sir.
137. Aayan Haider: Please send me two stage amplifier which output is 9.25dB gain
138. Cherukumudi Saisrividhya: tq sir
139. Nitin Bhardwaj: pls start the lectures on VLSI technology !!
140. Jiumiko TV: I do not understand the reverse saturation current, Icbo and Ico. @_@
141. sudipra biswas: Thnq.....
142. Manam VijayaChandra: The flow of electrons is from emitter to base....so the conventional current direction is from base to emitter....hence it is treated as a leaving current🙄🙄
143. Lavish KP: Sir please upload a video of Transistor Current Components.
144. Pranjal Kalita: Sir can you please also add lecture on voltage divider rule of transistor
145. I'll do it!: In Transistor Base Emitter Biasing (a) FB low resistance, RB High Resistance (b)FB High Resistance, RB low resistance (c) RB low resistance (d) Both FB and RB Sir what's the answer?
146. Suyash Gupta: How does decrease in recombination in base region results in the increase in Ie?
147. Manoj Kumar: Meghjit Mazumder thanq bro for the information
148. Lana Majeed: thank you 😢 I need it👍👍
149. Nando S: Very well explained. Thank you!
150. Vivek Kumar: TECH 25000V
151. Rituparna Modak: This is an seriously helpful vid i have seen ,all the confusions has been cleared out now.thankyou for the videos.
152. Other Guy: Puru Raj ya
153. sozol islam: the best academy is neso. thanks sir.
154. MD ZAKAULLAH: If its emitter current is greater than collector current than why are we saying emitter side is weak signal side..
155. Rony Macwan: KALYAN bro help me. left side me hi kyun Emitter Lia? two arrangements are possible
156. Elektronik Derslerim: thank you very much
157. mamini pradhan: sir.....when will u upload lectures on OPAMP ..... I need all lecture s related that ....and ...your way of explaining is superb...
158. Sapna Rahim: Thnks a lot sir u made it easy
159. harshit saxena: I think IE=IC+IB is also valid for saturation region but u told something else.
160. Masa Aq: we owe your or lives Thanks Sir
161. Vedant Majmudar: How Did We Get Ic = (alpha)Ib + Ico
162. Maai Cosinas: right
163. Asdf fdsa: Phalak Celly There will be no current supply if there is no load. Resistor used as load.
164. niranjana saravanan s: Sema sir... Tanq 4 te lecture... 🙏
165. s dhanalakshmi lakshmi: Your videos really very clear,. Thanks for your this videos., These are very helpful me for Ugc Net Exam.. But ,I have one doubt...mentioned as below.. Please , Explain Why in CB configuration, VCB plot gone to -ve side of axis..,? Thank you
166. Devavrat Somvanshi: we are not taking current from the output side. we are taking high voltage from output side.
167. Kshitiz Singh: how does Ico added to (alpha)Ibo in { Ic = alpha Ibo + Ico } ,while the directions of both are different ?
168. Anuranjana Singh: 👏👏
169. Varsha Shukla: y btao sr ki base to lower potential h fir current ground potential se kese flow ho rhi
170. Mfanelo Ngcongo: Sir. How is Ic the output current and Ie the input current when Ic enters the transistor and Ie is exiting ?
171. madamerotten: Αυτό είναι ελληνικό στο μυαλό μου.
172. Courtin Thibaud: How is possible that alpha (= hFE) remains constant as we control Ic and Ie ?
173. Bi-curious: why we ground the node in the cb transistor circuit, please answer?
174. baby Supraja: why current direction is always oppossite to electron direction
175. Sayyed Faisal: Why Resistance 'R e & 'R c'' is used ?
176. priya vishwakarma: Sir Why we have taken RC and RE???
177. Ritesh Choudhery: +yashitha Reddy start from scratch. Everything is available on the YouTube. And there is pretty sufficient time to prepare for it. Watch the videos,make schedule and you will be good to go.
178. ranga ramavath: What happened to base current in IE=Ib+Ic
179. Preeth Chill: Thanks sir u r the best
180. Devavrat Somvanshi: in this video, in Icbo , B stands for common base configuration, than why you use the same notation in common emitter video, i.e. in https://www.youtube.com/watch?v=IRok_SGrx9Q&list=PLBlnK6fEyqRiw-GZRqfnlVIBz9dxrqHJS&index=70 ?
181. mani kanta: current components is same alpha ,beta, gamma relation
182. Piyush Shukla: if Ic/Ie is less than one then it means output current is less than input current. then how is their any current gain.?????
183. satish vasamsetti: let us assume alpha=0.95 then the ic=0.95*ie...... so here output current is less than input current... so commonbase arrangemnt is not useful for ampilification ... am i right ?????????
184. Rajnish Chobey: Barsha Pati
185. Kanchan Attri: If R is neglected then why Vee =Vbe
186. Priya Sachdeva: Plz tell abt saturation region in common base
187. Ritesh Choudhery: Because emitter is highly doped thus offers low resistance and for amplification, we need the input resistance to be small and output resistance to be higher. So emitter junction is at left(low resistance) and collector junction is at right(High resistance). If you still have doubt watch this video it is explained. https://www.youtube.com/watch?v=yOmPCjPlaEg&index=65&list=PLBlnK6fEyqRiw-GZRqfnlVIBz9dxrqHJS
188. TECH 25000V: +Neso Academy why sir any issue why it is not possible...???? and so sir plz provide leacture on Microprocessor(for enginnering studen)
189. Cybernetic: love u sir please make as much video as you can
190. Asdf fdsa: GYAN PRAKASH Internally due to barrier potential.
191. Tea Man: Why are we not considering icbo for the base current?
192. Sumit Rangle: u said weak signal on input side and stronger on output side. But the gain itself is less than 1 it cant amplify!!!
193. Phalak Celly: Why have we added Re and Rc in this circuit?
194. Avishek Koirala: I wish my professor was clear cut like you professor. Hats off.
195. koko: I was asking te same question
196. Garikapati Anith Chowdary: if vcc is -5v how to equation
197. Anubhav Anand: Reverse current kyo hota hai detail me bataye please
198. Ritayan Mitra: Sir will u make lectures on "logic families" in this series? because this portion is very confusing
199. Divya Mishra: thanku sir it was very helpful
200. Bustana Tweene: Sir ,please upload power amplifier transistor...and its various types .....
201. Lakshmi: Why is the input taken across EB
202. Andromeda Black: Great videos. You are a life saver.
203. Funny Tv: Thanks sir.

Common-Base Configuration of a Transistor
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Education	Upload TimePublished on 3 Jun 2016