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Homework Statement
Determine the mode of operation of this npn BJT, given the terminal voltages.
E = -0.10 V
B = 5.0 V
C = 5.0 V
Homework Equations
Below
The Attempt at a Solution
According to the general rules, the EBJ is forward biased and the CBJ is reverse biased, leading to the...
i have posted the pnp npn and op-amp water analogies.
Could someone explain me pnp and op-amp water analogies.I have understood the npn water analogies but i have many doubts in it which i will ask after i understand pnp and op-amp water analogies.
eventhough the explanation is given in the...
Im working on a project that involves me making a electrical circuit that will supply initially around .52 amps of current for and then drop the current to at least .40 amps of current to a actuating wire that uses current to cause wire to contract. The way i have my circuit made is that i have...
this query was previously in electrical engg; later i found that it actually have to be solved as a solid state physics one.
(as in books) In an n-p-n transistor, emitter grounded, electrons enter the emitter from ground , where 90-98% come out of collector, and rest go out of the base.
In...
If we make an NPN transistor and change the base doping level so that we get a higher consentration of holes will β increase or decrease? Why?
I know β=IC/IB. Will more holes in the base make more electrons pass from the emitter to the collector increasing IC and thereby β? Or will IB...
in BJT transistors how can I find the maximum base current?
Do we have maximum voltage limitation for base of transistor? consider a resistor between input and base of transistor.
I want to use a transistor that its input range is from 3 to 30 volts and its output is 5 volts. how can i do...
Homework Statement
In circuit (figure), there is negligible potential drop between B and E, where β (current gain) is 100, calculate
(i) base current (ii) collector current (iii) potential drop across Rc (iv) Vce
(Ans: 11.25 µA, 1.125 mA, 1.125 V, 7.875 V)...
Hello everybody,
I'm currently taking Electrical Engineering as senior physics major at Fordham University and have decided to take on a little side project to gain a better understanding.
What I'm attempting to create is my own Transistor Logic -> RS-232 (Rs-232 refers to the serial...
Hi - I am looking for an NPN transistor with the lowest Vbe I can get.
Any suggestions for specific transistors? (rather than a material class i.e. GaAs)
I only have 3.1 volts on the collector and the emitter voltage has to be above 2.5 volts to get a circuit to trip. So 3.1v - 0.7v =...
Hey,
I would like help understanding this scenario:
(1) base-collector voltage, V_BC, is reverse-biased
(2) base-emitter voltage, V_BE, is forward-biased
(3) collector current, I_C, is negative
Normally, if I_C was positive, I would assume the transistor to be in the forward-active...
i have been trying to solve this problem for about 14 hours and have gotten nowhere, I am trying to figure out the voltage going into the base of an npn transistor, I am trying to build a circuit where i can take the current from the battery and build a circiut from 7npn transistors in a common...
Homework Statement
circuit diagram showing what has been identified as an NPN transistor with the collector and base connected to neg and emitter conected to pos. The base is also switched by a photodiode and the emitter is supplying a light bulb.Question asks when will the light come on.Can...
Is it the voltage divider and/or the Rc resistor that is responsible for biasing an NPN transistor. I am aware the role each play, but was just wondering which part actually biased the transistor, i wouldve thought both?
Hey guys, was just wondering if you could clear up some conflicting information i have found. In the v simply NPN transistor circuit, what is responsible for settings the quiscent point? Is it the voltage divider or Rc.
I no that the voltage divider ensures that the amplifier is 'switched on'...
Hey guys, sorry to keep posting things about the NPN transistor but i think I am starting to understand it. I was just wondering if you could confirm these facts for me:
1. An external powersupply is needed to turn the transistor on (by forward-biasing the emitter-base junction), or by using a...
Hey guys, was just wondering if you could clear up a fact about NPN transistors.
1. Is this emmiter current slightly larger than the collector current?
2. The reason why the emmiter current is slightly larger is because the emitter current is a combination of the collector current plus the...
Hey guys, i was wondering if you would be able to help me. I am currently in year 12 and am about to start learning about electronics. Part of the course is NPN transistors. I had read about 5 different books on how they work and yet i still dun understand them and how they work in a circuit...
What's about this? Where a capacitor is between base and collector (NPN). I have formulated some of my own theories (it seems like this is totally unknown of on the internet, and the books I've looked at don't explain it), but I have thought of flaws to all my theories. Can anyone please...
Homework Statement
an npn transistor is used to drive a constant current I through three ‘white’ LEDs, connected in series. If the required current value is I = 25 mA, and the current-gain of the transistor is β = 300, find the value of the resistor R, giving your answer to 3 significant...
Hi,
Could someone please help me with something i need to know to complete my college course?
The question says:
'Show with the aid of a circuit diagram and input/output waveforms how and NPN transistor can be used as a small signal amplifier, when operating in a common emitter...
The emitter current in a certian npn transitor is 8 mA. If .8% of the minority carrier injected into the base recombing with the holes, find the base current , collector current and the exact value of alpha
i am not sure how to get this started
thanks
joe