Nothing to work out, I gave a reference. I have a lot of books on theory that state what I showed, never seen your work. So as to which I believe, I'll stick with 30+ years experience and college. It's a no brainer guy.
I have never seen thermal effects used for feedback, but in this case it is regenerative (ie, positive), as temp goes up the collector current goes up. Not a valid arguement. The real increase in current swamps all your assumptions.
This equation has several holes.
Ic = β Ib
states otherwise. There is no connection between collector voltage controlling base current.
The correct equation is
Ib=(Vcc-Vbe)/Rb
I suspect you are thinking of this design:
I don't have the time or inclination to look up its bias formula, but it starts with Ic = β Ib, and adds the resistors effects. The emitter swamping resistor and base resistor divider are much more effective though.
I have never seen thermal effects used for feedback, but in this case it is regenerative (ie, positive), as temp goes up the collector current goes up. Not a valid arguement. The real increase in current swamps all your assumptions.
This equation has several holes.
False assumption there.2ndly, the base current is tied to the collector voltage, Ib=(Vc-Vbe)/Rb; and the collector voltage is tied to, among other things, the collector current: Vc=Vcc-Ic*Rload.
Ic = β Ib
states otherwise. There is no connection between collector voltage controlling base current.
The correct equation is
Ib=(Vcc-Vbe)/Rb
I suspect you are thinking of this design:
I don't have the time or inclination to look up its bias formula, but it starts with Ic = β Ib, and adds the resistors effects. The emitter swamping resistor and base resistor divider are much more effective though.
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