Someone remind me about this thread when I next tell people they need to understand Ohms Law and that it's pretty trivial
After Bob's last post I did a search "AC Ohms Law Origins". I was hoping to attribute a name in connection with Z concepts. According to Wiki, It seems to fall under Maxwell's Equations.
Ohms law states that the voltage and current are proportional. They are not in an inductor, capacitor, transistor, diode, neon light, triac, diac SCR. So if you are agreeing with the statement that I challenged, "All components obey Ohm's law", you have a lot of work to do.
Bob
For Inductors and Capacitors, they are but 90° out of phase.
As for the other components listed In there you have to factor in the context in which I made that statement. If you recall I was working with a young fellow building a 12AU7 amplifier. Note that I said "governed", not "obey".
Originally Posted by Solidus
I was asking if plate-load resistors have an analog in transistor-mediated circuits.
(solidus)
Sure they do. For BJT's it's the "Collector Resistor". It doesn't matter if we're talking Tubes, BJT's, MOSFETs, JFETs, Resistors, Light Bulbs, Inductors, Capacitors or even Wire. All components in an electronics circuit are governed by Ohms Law.
Chris
That statement was made in the following context:
An Instructor draws a BJT (Q1) amplifier on the black board. It includes an Emitter Resistor (Re), Collector Resistor (Rc), Base to GND Resistor (Rbg) and a Base to Vcc Resistor (RbVcc). The instructor gives the class the value of only one Resistor, the Emitter Resistor (Re) = 100R. The Instructor then writes the following on the board Vcc = 12V, Q1(hFE) = 100, Ic = 5mA, Vc = 6V. Solve for the values of Rc, Rbg, RbVcc. I_Rbg = 10 x Ib.
These students will most definitely utilize their new found skills with Ohms Law to solve this class work. In the end the behavior of Q1 is most definitely governed by Ohms Law.
There may exist a component that I can't spin into an Ohms Law scenario like this but, off hand, I can't think of one.
Chris