Hello.
I'm trying to get back to the basics of BJT transistors. This is no homework. Just me trying to get back to the basics.
I want to write the net equations and node equations but there are a few things that are forgotten and I'm struggling a bit to get them back to my mind.
I'm using Qucs to simulate the circuit. I'm not sure it's files are compatible with LTSpice which I know is probably more common around here than Qucs but I'll upload the files here.
I want to calculate all resistor's voltage drops and currents of interest so that I can compare them with Qucs results.
This is the circuit.
I think I can write the following equations but I'm not sure they are correct
\( \displaystyle{I_{R_{1}} = I_{R_{2}} + I_{b} } \)
\( \displaystyle{12V  V_{R_{1}}  V_{R_{2}} = 0} \)
\( \displaystyle{0.7V = V_{R_{2}}  V_{R_{3}}} \)
\( \displaystyle{12V = V_{R_{c}} + V_{R_{L}} + V_{LED}} \)
\( \displaystyle{12V = V_{R_{c}} + V_{CE} + V_{R_{E}}} \)
Now, are these equations all good? Can I discard anyone or I'm going to need them all?
I'm trying to get back to the basics of BJT transistors. This is no homework. Just me trying to get back to the basics.
I want to write the net equations and node equations but there are a few things that are forgotten and I'm struggling a bit to get them back to my mind.
I'm using Qucs to simulate the circuit. I'm not sure it's files are compatible with LTSpice which I know is probably more common around here than Qucs but I'll upload the files here.
I want to calculate all resistor's voltage drops and currents of interest so that I can compare them with Qucs results.
This is the circuit.
I think I can write the following equations but I'm not sure they are correct
\( \displaystyle{I_{R_{1}} = I_{R_{2}} + I_{b} } \)
\( \displaystyle{12V  V_{R_{1}}  V_{R_{2}} = 0} \)
\( \displaystyle{0.7V = V_{R_{2}}  V_{R_{3}}} \)
\( \displaystyle{12V = V_{R_{c}} + V_{R_{L}} + V_{LED}} \)
\( \displaystyle{12V = V_{R_{c}} + V_{CE} + V_{R_{E}}} \)
Now, are these equations all good? Can I discard anyone or I'm going to need them all?
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