I'm working on a problem in Chapter 8 of Malvino/Bates "Electronics Principles", and one in particular is driving me nuts.
In this problem, we start with a VDB (voltagedivider bias) and open the R2 resistor; the result is essentially an emitterfeedback, with the BJT saturated.
There is an example that specifies expected voltages at the transistor's connections for this situation, as well as a problem which does the same thing with another example, and I can't seem to calculate voltages for either example that makes sense. I've tried it a number of ways using the equations in the chapter.
Attached are two screencaps from Paul Falstad's applet that I was using to visualize things. For the "normal" one, I have no problem getting matching numbers, but for the R2open one, I'm stuck  I'm not clear on how the saturated transistor gives the numbers shown.
Could someone give me an example of getting the voltages at CBE in the "r2open" attachment?
Note that the applet's model is using a Vce of about 0.6v rather than the "standard analysis assumed value" of 0.7v, but that still doesn't give me reasonably close numbers using the "emitterfeedback bias" equations from the book.
In this problem, we start with a VDB (voltagedivider bias) and open the R2 resistor; the result is essentially an emitterfeedback, with the BJT saturated.
There is an example that specifies expected voltages at the transistor's connections for this situation, as well as a problem which does the same thing with another example, and I can't seem to calculate voltages for either example that makes sense. I've tried it a number of ways using the equations in the chapter.
Attached are two screencaps from Paul Falstad's applet that I was using to visualize things. For the "normal" one, I have no problem getting matching numbers, but for the R2open one, I'm stuck  I'm not clear on how the saturated transistor gives the numbers shown.
Could someone give me an example of getting the voltages at CBE in the "r2open" attachment?
Note that the applet's model is using a Vce of about 0.6v rather than the "standard analysis assumed value" of 0.7v, but that still doesn't give me reasonably close numbers using the "emitterfeedback bias" equations from the book.
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