All Questions
13
questions
4
votes
1
answer
655
views
BJT Is Saturation current temperature dependence singularity
So, I am currently looking at the ways transistors change their parameters with temperature according to SPICE for a thorough investigation of synthesizer VCO exponential converter. Particularly, the ...
- 1,109
0
votes
0
answers
49
views
How to add transistor model to LTspice? [duplicate]
So, I'm an absolute beginner at LTSpice(I just started today).
I want to know how to add the model of transistor(say model ZTX300 or BC108) to my schematic.
I can't find the model in the standard.bjt ...
- 1
0
votes
2
answers
137
views
Help understanding BJT active load SPICE model parameters
Why would Q3 and Q4 not have the same BF values in the picture of the Spice model i have attached?
- 21
0
votes
3
answers
714
views
Where does Zi = hie+1(1+hfe)RE come from in a BJT from Hybrid Model?
I've been struggling to understand how to get to this expression without knowing about re model (actually, still knowing about it, I can't get to understand this).
In a BJT in, how does one get to Zi ...
- 298
0
votes
2
answers
2k
views
BJT AC Analysis using r_e model
This is a picture of a Common Emitter Voltage Divider bias and it is been modelled using a CCCS and a diode resistance using the r_e model. Now my doubt is that I get problem in finding the input ...
- 49
5
votes
1
answer
595
views
Operation of BJT with low values of Vbe ("cutoff" region)
Many sources claim that when the base-emitter voltage becomes smaller than approximately 0.6V-0.7V, the bipolar junction transistor goes in the cutoff region and there is zero base and collector ...
- 163
-1
votes
2
answers
537
views
How to double the collector current of a BJT in LTSpice?
I am trying to model a multi-collector lateral PNP in LTSpice. The link here suggests to put 2 PNP transistors in parallel and split up the IS into two parts.
http://pallen.ece.gatech.edu/Academic/...
3
votes
3
answers
2k
views
How is possible that with same Ibase there is more than one Vce?
Ok guys, look at this picture:
How is possible that with the same \$I_{\rm base}\$ we have more than one \$V_{\rm ce}\$?
- 327
1
vote
2
answers
178
views
Hybrid parameters vs. frequency
The question I need to solve is: how do the h parameters (hybrid) vary as a function of frequency?
In particular, I need to estimate the Y parameters (admitance parameters) for a 2N3904 transistor, ...
- 3,044
0
votes
3
answers
12k
views
r0 vs ro in transistors ac modeling?
I'm a beginner in electronics field . In hybrid and pi and T models we have a resistance called r0 or ro . What's the correct name ? Is it "r-zero" or "r-o (15th alphabet letter)". Pls give ...
3
votes
2
answers
1k
views
Measuring BJT (Ebers-Moll) parameters
I am currently attempting to measure the parameters of a "vintage" germanium BJT in the hope of creating an Ebers-Moll model from the data. So far I have been unable to find a comprehensive source on ...
- 1,856
4
votes
2
answers
3k
views
Av for small signal analysis with BJT for unbypassed emitter and ro in place
My question is about another question on this site. On that question Z(in) for small signal analysis with BJT for unbypassed emitter and r0 in place Zin is asked for a common emitter configuration ...
user57823
2
votes
3
answers
11k
views
Z(in) for small signal analysis with BJT for unbypassed emitter and r0 in place
I have been studying the small signal analysis of BJT with re model with the emitter terminal not bypassed. I am able to derive those Zi, Zo,Av, Ai long as ro is assumed to be infinite. But I am ...
- 181