Hi,
before you proceed with reading this question, I would like you to know what I do not expect anyone to solve this task for me. I have a problem with a single step in the solution and I'm only asking you to help me with this one step.
1. Homework Statement
Compute ##R_B## so that Q-point of...
1. Homework Statement
I'm studying a circuit with BJT's and I'm asked to determine the input resistances of the two amplification steps of the circuit. The circuit I'm analyzing is the following one:
2. Homework Equations
3. The Attempt at a Solution
To determine the input resistances I...
Hey guys, I'm confused as to the difference between the h-parameters usually given by datasheets and their hybrid-pi model analogues. For instance, I know hfe = Beta in small signal analysis, but what about the other h-parameters.
Thanks for any help with clarifying this.
Hey everyone,
I'm trying to plot a straight line for a bipolar junction transistor to find the room temperature, T, using my experimental results for the associated base-emitter voltage, ##{V}_{BE}## and collector current, ##I_C##. Here's the equation that I'm using:
$$ I_C = α_F {I}_{EO}...
This is what I have and I was wondering where C2 might go if I make apply the hybrid pi model on this circuit. I know that all the DC Voltages should be shorted if I were to make use of an equivalent circuit, so that in the hybrid pi model R1 should be in the input and R3 in the output. But what...
How am I supposed to calculate ohmic resistance from a non-linear electronic device component?
Say, for example, I need to calculate ohmic resistance of a pn junction of bipolar junction transistor from its forward I-V characteristics curves. (It can be either Base-Emitter junction or...
For the B) part, I don't get why is it that for calculating voltage between collector an the emitter (Vce) I take into account diode on base (0.7V), whereas for part A) it's ignored?
Why is Vce in part A and part B are calculated differently? Why is it that in part A voltage of 0.7V isn't taken...
1. Homework Statement
I have been given the world's longest transistor problem as an assignment :wink: Here is the circuit:
I am asked to find:
a) V1, V2 and V3 using DC analysis
b) AC equivalent circuit
c) AC tension gain: Ava=Vx/Vsig
d) AC tension gain: Avb=Vo/Vx
e) Total AC tension gain...
1. Homework Statement
For beta = 100 and assuming ro is very large, what is the DC voltage at the collector?
2. Homework Equations
IB = IE(β+1)
IC = β*IB
3. The Attempt at a Solution
Since IE = 0.5mA, IB = 0.0505 A
Then, IC = 5.05 A (which doesn't feel right)
VC is the same potential...
I don't know how to calculate the voltages at the bases of every transistor shown in the lower row of that picture (~3V (2.9..V), ~2V, ~1.8V). Any help would be appreciated! - I'm currently trying to figure that out...
The other thing I don't really understand: Why do the transistors in the...
<< Obnoxious all caps post fixed by Moderators >>
I have made an audio amplifier using an LM386 IC, but it does not amplify any sound from the microphone. Please help me to improve this using a Darlington pair or any other power transistor like the TIP147/142...
I need help in making my project using Bipolar junction transistor. I'm Engineering student (Ist year). Can someone here suggest me a Funtastic project that i can make easily and impress my teachers as well using BJT transistor. I have rea the Cascade, cascode and Darlington technique to amplify...
Please help how Ve is calculated what i think is that it should be:
-Ve=-Vee+IeRe;
How Ve is taken positive please someone draw equivalent circuit for same
1. Homework Statement
In my book ,I found this line which says ,"The collector current comprises two components-the majority and the minority carriers .The minority-current component is called the leakage current and is given the symbol ##I_{CO}## .The collector current, therefore is determined...
In BJT hybrid pi small signal model, we have a resistor "ro" between Collector and Emitter.
This resistor is to include the change in collector current when there is a small signal voltage change between collector and emitter. (due to early effect)
I am finding that all BJT hybrid small...
I'm having the worst time ever with a two stage cascode bjt amp. See attached circuit image. In the circuit photo the "In R: 168ohm" is the amps input resistance according to LtSpice. I usually have luck with LtSpice. The circuit shows real measured resistor values. I built a LtSpice version...
1. Homework Statement
hello, i need to design analog circuit that has a transfer curve as seen in the following image using resistors, capacitors,voltage, and BJT (with beta value of 100).
the parameters are:
A=75
f1= 21Hz
f2=21 KHz
M1=40
M2=-20
the circuit also need to have input resistance...
Hey there, I want to build a simple temperature sensor using a BJT (BC547, 2N2222, or similar). I'm not sure how should I do that. My first thoughts where: measuring the Vbe, using around 9v to 12v as Vcc, the transistor with common-emitter; then just wrap the transistor in plastic or...
I have been checking the BJTs on a car audio amplifier board with my DMM's diode test feature, and I need a little help understanding something I have been noticing:
The base to emitter and base to collector voltage drops are present, and show an open circuit when the leads are reversed as they...
1. Homework Statement
It is required to design the bias circuit as shown in figure for a BJT whose nominal {\beta} is 100.
a.) Find the largest ratio {(R_B/R_E)} that will guarantee {I_E} remains within 10% of its nominal value for B as low as 50 and as high as 150.
b.) If the resistance...
So, recently I started learning about electronic components and then I started learning about semiconductors. The one which I've been having some real trouble to understand its function is the transistor.
So I bought an electronics textbook called El ABC de La Electrónica (The ABC of Electronics...
Hi i have have a small question regrading to a NPN BJT transistor.
the DC current gain (beta) is the ratio between Ic/Ib where Ic and Ib are the collector and base currents respectively.
Ib is the input current, thats alright , but, i dont get why Ic considered as the output?
in NPN BJT...
So far the explanation on BJT working principle always explained in electron flow perspective.
I felt it's hard to relate with conventional current direction notation when the explanation explained in electron flow direction notation. For example in NPN transistor, the C-E current flow made me...
Hi everyone. im starting to study transisors at Uni. and im confuse in some main concepts. i thought about posting it here so someone can help me up. are pi hybrid signals equivalent circuits used with the same porposes as small signals equivalent circuits? or are pi hybrid signals, small...
so i know that h11 is defined as v1/i1 when v2=0 and so on...but the thing is how do i do it practically...my professor told me that v1,i1,v2,i2 in h parameter equations are instantaneous values of current and voltage of ac in a bjt. he even wrote that to get h11, you have to set v2 of ac=0. but...
Hello,
I am reading The Art of Electronics, and I have two specific questions regarding examples it has introduced. I am dealing with bipolar transistors the current chapter. I think my questions mostly stem from not understanding concepts.
The text has introduced the technique of...