Dears, I found the following in this page In the attached file, which I need your confirmation if what I think is true or not. I believe the marked should be RE
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Correct, and the "Table below", isn't even a table.Also here:"The value of internal resistance RE is a function of emitter current IE, Table below. ""RE" should be "REE".
I'm not trying to be picky -just helping-, but now that you mention the tables, when I reached the next one at a first glance I got the impression that "Bypass Capacitor for RE" was the table caption instead of the title for the next section; as it's right under it without any separation line.Correct, and the "Table below", isn't even a table.
... and then further down without it...Thus, for the common-emitter circuit Rin is
Rin = βREE/IE
Shouldn't it be always "Rin = βREE", without the "/IE"?Rin = βREE = 100(26) = 2600Ω
I don`t like at all the usage of REE.Also here:"The value of internal resistance RE is a function of emitter current IE, Table below. ""RE" should be "REE".
May I add another point?Yes, that happened to me: the first time I came across "REE" I had no idea it was a dynamic resistance. But I already knew that when I read the "Biasing Calculations" chapter.
Thanks mnada for the nice attachment, Which made it easier to make the change at ibiblio.
Not sure you might also want to correct a small typo I found in this chapter; it's nothing important. In the second line of the Emitter-bias formulas the first "β" is written with a lowercase "b":
emitter resistor replaced by base resistor as proposed at ibiblioI think I found 2 more in that same chapter....
The first is in this paragraph:"How can we improve the performance of emitter-bias? Either increase the emitter resistor RB or decrease the base-bias supply VBB or both. As an example, we double the emitter resistor to the nearest standard value of 910Ω."In which I think "RB" should be "RE"
And in this paragraph:"As an exercise, rework the emitter-bias example with the base resistor reverted back to 470Ω, and the base-bias supply reduced to 1.5V."I think it should read "emitter resistor" instead of "base resistor".
Changed to REE as proposed at ibiblio.orgAlso here:"The value of internal resistance RE is a function of emitter current IE, Table below. ""RE" should be "REE".
Added a bigspace tag to the source at ibiblio.org to correct this.I'm not trying to be picky -just helping-, but now that you mention the tables, when I reached the next one at a first glance I got the impression that "Bypass Capacitor for RE" was the table caption instead of the title for the next section; as it's right under it without any separation line.
I deleted the "/IE" from the line in the copy at ibiblio.org .I think I found a minor mistake in the "Amplifier impedance" chapter; though maybe I'm wrong.
I'm not sure if this formula is right. You wrote it first with the "/IE"...
... and then further down without it...
Shouldn't it be always "Rin = βREE", without the "/IE"?
I don`t like at all the usage of REE.
I know what it means (it is 1/gm=Vt/Ic), however there is one general and important rule:
Don`t mix ohmic (static) resistances with dynamic (differential) resistances.
This of extreme importance for understanding all circuits involving non-linear parts (diodes, transistors).
Thus, all differential parameters should carry SMALL letters and we always should write rEE.
EDIT: Using this unfortunate symbol REE the gain of an emitter stage is
G=-Rc/(REE+Re)
Thus, it looks as the gain is simply determined by ohmc resistors following Ohm`s law.
According to my experience, some beginners indeed were following this false approach.
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