I'm having trouble analysing this circuit and was hoping someone could help me. The circuit in question is below.

enter image description here

I want to find the voltage drop and current across each of the parts. So far I've found the thevenin equivalent:

enter image description here

I'm a little confused as to how to find the current. Would I simply use $$\frac{11.2V}{13.33k\Omega}?$$

Or does the diode subtract 0.6 or so volts from the total voltage to be $$\frac{10.6V}{13.33k\Omega}?$$

  • \$\begingroup\$ The second is correct \$\endgroup\$ – Simus994 May 2 '17 at 20:42
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    \$\begingroup\$ And the next step would be to verify this current will actually make the diode into a region where it has the forward voltage drop you have assumed. \$\endgroup\$ – Eugene Sh. May 2 '17 at 20:44

Follow the arrows below. The first transition is due to making a Thevenin equivalent out of \$V_1\$, \$R_1\$, and \$R_2\$. The second transition is just summing the remaining two resistors:


simulate this circuit – Schematic created using CircuitLab

There will therefore be about \$600\:\textrm{mV}\$ subtracted away from the Thevenin voltage, leaving \$5\:\textrm{V}\$ across the total resistance of \$10\:\textrm{k}\Omega\$. About \$500\:\mu\textrm{A}\$.

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  • \$\begingroup\$ Comments are not for extended or off-topic discussion; this conversation has been moved to chat. \$\endgroup\$ – Dave Tweed May 2 '17 at 22:07

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