Transistor Base Bias Circuits - Finding The DC Load Line & The Q Point Values
Vložit
- čas přidán 26. 02. 2020
- This electronics video tutorial provides a basic introduction into transistor base bias circuits. It explains how to find the DC load line and the Q-point values for Ic and Vce.
Transistors - NPN & PNP: • Transistors - NPN & PN...
BJT Transistors - Electronic Switches:
• BJT Transistors - Elec...
Night Activated LDR Sensor Circuit:
• DIY Night Activated LD...
Voltage Divider Bias Circuit:
• Voltage Divider Bias C...
Collector Feedback Bias Circuit:
• Collector Feedback Bia...
__________________________________
Emitter Feedback Bias Circuit:
• Emitter Feedback Bias ...
Common Emitter Amplifier:
• Bipolar Junction Trans...
Common Collector & Base Amplifier:
• Common Collector and C...
Darlington Pair & Beta Current Gain:
• BJT Transistors - Darl...
Class A, AB, B, & C Amplifier Circuits:
• Transistor Amplifiers ...
Voltage Gain of Transistor Amplifier:
• How To Calculate The V...
_________________________________
Multistage Transistor Amplifier Circuit:
• Multistage Transistor ...
Transistor Audio Mixer Circuit:
• Transistor Audio Mixer...
Operational Amplifiers:
• Operational Amplifiers...
Summing Amplifiers:
• Summing Amplifiers - O...
LM386 Audio Amplifier:
• LM386 Audio Amplifier ...
LC Oscillator Tank Circuit:
• LC Oscillator Tank Cir...
_______________________________
Final Exams and Video Playlists:
www.video-tutor.net/
Full-Length Videos and Worksheets:
/ collections
Final Exams and Video Playlists: www.video-tutor.net/
"The Organic Chemistry Tutor"... Kind of a trademark name for a chemist handling physics so exceptionally! Thanks a lot for all these years... Please never stop.
I’d be happy if my semiconductors professor was a tenth as good as you at explaining this stuff. Excellent video!
Can't count how many times this channel has helped me out
Good problem solving sessions ,a kind request to keep more of these ,these are lifesavers! Thanks man..
Great tutorial in physics by a chemist! Who knew that you can top them all?! Thank you for the detailed explanation. Your great effort is much appreciated on this critically important and versatile component.
Thank you for this video. I have used a lot of your videos in my physics classes. It has inspired me to create my own channel for my physics students. They are loving it. Please don't stop.
post more content on your channel! We can never have a shortage of well-explained physics concepts, especially for EE students like me!
This is the clearest explanation of DC load line I've heard!!! Great content!!! THANK YOU!
I have watched so many videos on q point but this one i can perfectly understand.
Very nice explained, I have Q-Point in my pocket now!
Very well done - to the point, well described and easy to follow!
So helpful, man. Thank you very much for this video! Keep up the good work.
Very clearly presented, easy to follow. Thanks!!
I really hope you can make a series of tutorials about the AC circuit . thank you so much for helpful content
I have presentation about this topic and i finally understand and got present very well thankyouu man you saved me
great to learn or relearn video.... nice to re-see this q-point info before making an arduino circuit... thanks a lot...:)
Priceless video!! Thanks!
You are being led down the garden path.
Beautifully explained. I find myself rewatching and reannotating your videos, lol. Taking more notes in case I missed anything.
One question I have is, how is this applied to amplifiers? Can I just use this method and plug my guitar or a line-level signal into the base and expect an optimal amp or is there way more to it?
awesome content
This is quite helpful. Thank you very much!
This is a video on how to plot dc loadline: czcams.com/video/Rqpiz6_3OUw/video.html
lovely stuff
What! Incredibly excellent!
Excellent video - a clear explanation on BJT biasing circuits.
You are being led down the garden path.
Perhaps I'm biased after watching some of your other content, but I think this video was loaded with with information that was truly on point!
Did not have much knowledge about transistor, but this video enlightens me much. Great job!
I havn't watched this video yet, but oh my god man i know you'll help me out with this cause my professor explains like we understand xD, thank u for being of help
Your a life saver
Thank You !!
Thank you, you saved my life
You are being led down the garden path.
Thank you
i hella love you man
Thank you bro
Helpful
Thanks 🙏👍💯😊
brilliant
Thanks for the video
Please i wish to know the software you used in writting in your video
How about common colector for increase current, is the q point and dc load still be calculated?
In the analysis of circuits that make use of resistors, diodes and transistors, it is
necessary to determine the operating point (voltage and current) of the device connected
in a network, which is made from devices whose parameters are known.
It is often necessary to determine voltages between terminals of a network with no current flowing.
Consider for example the network which consists of two resistors R1 (terminals marked A and B) and R2 (terminals marked C and D). Their ends (A and D) are connected to the positive and negative terminals respectively of a power supply of 12 V dc. The other ends of the resistors are left unconnected.
Suppose that the resistors R1 and R2 are 10 ohms each.
What will a voltmeter read if it is connected between terminals A and B?
What will be the reading of a voltmeter connected between the terminals C and D ?
What will be the reading of a voltmeter connected between the terminals B and C ?
Electrostatics and circuits belong to one science not two. To learn the operation of circuits, Current and the conduction process, resistors, capacitors and inductors and how discussing these topics with a unified approach makes it easier to understand how there is a voltage of a single wire connected to one terminal of a battery watch these two videos
i. czcams.com/video/TTtt28b1dYo/video.html and
ii. czcams.com/video/8BQM_xw2Rfo/video.html
The last frame References in video #1 lists two textbook 4 includes topics that discuss simple networks and the physical processes which causes the appearance of potential drops.
Specifically, in Chapter 3 discussions of load line graphs both dc and ac and their use in fixing the operating points of devices such as resistors, diodes and transistors are included.
We continue for now with a brief discussion of the cause of the voltages between the dofferent terminals of the network example in this post.
When the network is made, electrons will enter the battery positive terminal and the potential of the resistor R1 would have been raised. The battery positive terminal, would drop in potential due to the neutralising action of the few electrons, but then its chemical
action will quickly restore its potential difference (p.d.) to 12 volts. The migration of electrons will stop, when the potential of the resistor equals the battery positive potential.
And all this happens within a few picoseconds. There will be a few surface charges on the resistor R1, and these indicate its new status of potential.
It should be clear that a voltmeter when connected between terminals A and B of circuit will read ‘0’ volts, because the potential of the resistor R1 and the battery positive, will be the same, namely, 12 volts. In the case of the resistor R2 connected to circuit zero, a few electrons would have entered the wire and the resistor R2 from the negative terminal of the power supply which is circuit zero, making the potential of the resistor R2 the same as circuit zero. There will be a few surface charges on the resistor R2 that indicates
its new status of potential. A voltmeter when connected between terminals C and D of circuit will read ‘0’ volts, because the potential of the resistor R2 and the battery negative will be the same, namely ‘0’ volts.
The current in the circuit will be zero because of the open circuit.
Since the potential of terminal B is the same as that of A, its potential is 12 volts.
Since the potential of terminal C is that of the battery negative or circuit zero (terminal D), it is ‘0’ volts. Therefore, a voltmeter connected between the terminals B and C will read
the same p.d. as that between the terminals A and D namely, 12 volts. We can allow a current to flow in the circuit by simply connecting a wire between
terminals B and C thus, short-circuiting them.
The current in that case will be 12 V/(10 Ω +10 Ω) = 12 V/20 Ω = 0.6 amps.
The two points marked on the x- (voltage) and y- (current) axes are joined together, and this line is called the “Load line” of the network. The load line is the locus of points, or pairs of voltage and current values for the voltage between terminals B and C and the current in the circuit, when the terminals B and C are bridged by a resistance. The load line is fixed for a fixed power supply voltage and fixed values of resistors R1 and R2.
AC load line
Circuit analysts usually draw ac load lines during the design phase of transistor amplifiers. In Section 3.4, Chapter 3 of textbook 4 in References in last frame of Video #1 more details including diagrams of the analysis of circuits using dc network load lines are provided. In the question Q.3.1 in the file "Additional Practice Questions for all chapters" in the CD with this textbook 4, a description of ac load lines is provided, which would be useful to read. Space does not permit a full discussion in this post.
What software do you use to draw all that ?
Can we use the information on the datasheet to design an amplifier?
would it make difference if there was a RE resistor and R2 resistor under RB ?
ty OCT!
perfect
When Vce comes negative...how will be the dc line...or the negative sign doesn't affect?
the best
TNAK YOU
Hello. are your playlist organized? like the first video is lesson 1 and the next video is lesson 2 like that
i love how he teaches everything although his name is organic chemistry
There are 2 ways to bias the transistor...one way is to set Vce to half the supply voltage. The other way is determine Vce sat and Ic max then look at the middle Q point operating on the graph of the transistor characteristic. From that find the nominal hfe.
does q stand for quiescent? so the quiescent voltage is the voltage at the q point?
11:45 is it always true - "potential between C and E is = half of Vcc" or in this particular example?
Thats for a centered q point
i wish if my teacher is as good as you
👍
Can you do this video with PNP transistor
Is Vbe and vb the same?
DO you have a powerpoint for this one?
how could we know that the IC value we choose is in the appropriate region ??
Do ACLL please
From india 👍❤️🇮🇳
Can we take beta value as random like 100,150,200..🤔
No it is given in the question
@@thelegend2543 but what if it's not given in the question?
Pleass neam program
ight
organic chemistry hmm interesting
I don’t know but m more confuse 😢
H
Hi