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Main Question or Discussion Point
I am NOT trying to solve this as a homework problem, I'm just trying to dig out basic concepts that I'm missing when using this battery+resistance diode model.
I'm having trouble seeing why, when solving for current, KCL equation does NOT work out as:
1) I= (0Va)/rd
2) I=(Va(5))/R
where Va is the voltage at node a, rd is the diode resistance, and Vd0 is the diode voltage drop.
I understand that the resistors are in series, and there is only one current, so the correct Kirchoff's equation should be:
I=(0Vd0)/(rd+R)
But each resistor is responsible for a (different) voltage drop. The position of the resistors, even if they are in series, is specific. We can see this by measuring voltages before and after a resistor. Hopefully somebody can provide a fullproof explanation for this.
I'm having trouble seeing why, when solving for current, KCL equation does NOT work out as:
1) I= (0Va)/rd
2) I=(Va(5))/R
where Va is the voltage at node a, rd is the diode resistance, and Vd0 is the diode voltage drop.
I understand that the resistors are in series, and there is only one current, so the correct Kirchoff's equation should be:
I=(0Vd0)/(rd+R)
But each resistor is responsible for a (different) voltage drop. The position of the resistors, even if they are in series, is specific. We can see this by measuring voltages before and after a resistor. Hopefully somebody can provide a fullproof explanation for this.
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