Hello, good morning.
Im new to Qspice and electrics, and Im trying to draw the diodes curve, but the current values are not going wright. Then I cant find the correct charge line and points(saturation, cut)
May some one help?
Reduce the pitch from 0.5V to 10mV.
1 Like
Seems wrong compared with the book I have. Here is the circuit:
The Q(operation point) is marked in 12.5mA. My simulation is giving 2.6 mA
Results:
Just one doubt. Why r and d must be in parallel? Did I missed something in theory?
You setup D and R in parallel, this is to plot their load line, but NOT solving the circuit with D and R in series. Load line represents the I-V characteristic of the diode and resistor, where the operating point Q of D and R in series is the intersection point of their I-V curves.
In Qspice, you won’t find this load line, load line is textbook method explaining how to resolve operating point of a circuit with non-linear elements; in SPICE, it directly calculates the Q point, as the circuit can only have one solution, and not giving you the load line.
Therefore, don’t mix up the solving method with the solution.
Here is to solve Q point of D in series of R
At your first post, when you sweep the V1 from 0.5V to 2V, what you are doing is to resolve this circuit operating point at different input voltage, what you get are Q-point at different input voltage.
1 Like
Hi, good morning. I pretty apreciate.