So basically we can have a constant current but i don't understand this circuit.
for example: i can have the Ia what ever I want with current divider rule: Ia = Iq * R2/R3. So Ia is proportional to the ratio of R2/R3.
And if i give a resistor at the collector terminal, if i change it between...
Summary:: So apparently the equations schould be correct but I am not sure about it.
Isnt R1 = Ub(10V) - Base voltage / Iq + Ib --> Ub is the source voltage 10V.
And schouldnt R2 be :base voltage / Iq?
First the hybrid model, I assume the capacitor works as a short circuit regarding the altern current:
$$A_V=\frac{v_o}{v_i}$$
$$v_i=-v_{GS}$$
$$v_o=-i_LR_L$$
$$i_L=g_mv_{GS}+\frac{v_{DS}}{r_d}$$
Now I use the Kirchhoff's law to get $v_{DS}$. I consider this close loop:
$$-v_i-v_{DS}+v_o=0$$...
Hi, I have a circuit with 3 transistors I want to rewrite to a small signal model. When multiple transistors are in the circuit I get confused how to do it. This is the signal model and small signal model I have. Is it wrong?
##V_{BE}## is basically the difference in voltage between the base terminal and the emitter terminal.
Normally when silicon is used and the transistor is biased to operate in the active region, ##V_{BE}## = 0.7 V approximately.
The way I understand this is that for an npn BJT, the applied...
This is the given schematic. The result should be $$A_u = \frac{R_b g_{21}}{1 + R_b g_{22}} = -50$$ and the way I wanted to tackle this problem is by stating $$A_u = \frac{-R_b i_2}{u_1} = \frac{-R_b (g_{21} u_1 + g_{22} u_2)}{u_1} = \frac{-R_b (g_{21} u_1 + g_{22} u_2)}{g_{11} u_1 + g_{12} u_2}...
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.
I am attending an online lecture course on semiconductor physics. While explaining the common emitter mode of transistors, the professor sketched this diagram on the board: (I added something more to explain better)
I understand that the emitter has to be at the same potential, and that is...
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...
Thank you for reading my post. I'm currently studying Op-amp, and there is a homework about LH 0005 of National Semiconductor for me to do: determine the collector current through each transistor
I'm trying to find the IC2 but don't know how. Please help me with this :)
Homework Statement...
Recently I started studying semiconductors and analogue electronics. First I studied the diode and its I-V characteristics and analysis in DC circuits, as well as in AC circuits.
Now I started with BJT transistors. I was explained that transistors act as electronic switches. My problem is not...
Homework Statement
I’m having trouble with analysing the transistor circuit attached to find VC, VB, VE, IC, IB and IE.
Homework Equations
These equations are taken from a previous example
VE = VBB – VBE
IE = (VBB – VBE)/RE
IB = IE/β+1
IC = β/(β+1) x IE
VC = VCC – ICRC
β=100...
Homework Statement
Just started learning about transistors, and I am having difficulty doing this problem.
The transistor in the circuit has k_n ^'=0.5mA/V^2, V_t=0.5 V, \lambda =0.
Show that operation at the edge of saturation is obtained when the following condition is satisfied...