Diode Circuits part 2 | Real Diode Model & Small Signal Analysis | 5 Regions of I-V Curve + Example

In this video, we take a complete look at the real diode model and how to perform small-signal (AC) analysis in diode circuits — starting with a full breakdown of the diode's characteristic curve regions, and finishing with a fully worked circuit example. 🔹 What you'll learn in this video: ✅ A complete breakdown of the 5 regions of the diode I-V curve: cutoff (0 to V_γ), forward conduction (exponential), the curvature/knee region (small negative voltage with a different slope), reverse-bias saturation (roughly constant −I_S), and the breakdown region ✅ Why the exponential relation still holds in the curvature region, just with a different slope ✅ The small-signal model: splitting the diode's total voltage and current into DC and AC components (V_D = V_DC + v_ac) ✅ Why an OFF diode is treated as an open circuit in the AC domain ✅ Why an ON diode is replaced with a dynamic (small-signal) resistance r_d in the AC domain ✅ Full derivation of the dynamic resistance formula: r_d = ηV_T / I_DQ ✅ A fully solved circuit example: finding the DC operating point (Q-point) using the load line method ✅ Complete AC analysis of the same circuit — replacing the diode with r_d and the capacitor with a short circuit — and precisely calculating the output voltage V_out This video is perfect for electrical and electronics engineering students studying advanced diode circuits, operating point analysis, and circuit design — it teaches exactly the tool you need to analyze any diode-based amplifier or signal-processing circuit. 📌 If you found this video helpful, please like it, share your questions in the comments, and subscribe to the channel for more electronics tutorials and solved circuit problems. Turn on the 🔔 bell so you don't miss future videos. #DiodeSmallSignalModel #DynamicResistance #LoadLineMethod #ElectronicsTutorial #ElectricalEngineering #Diode #QPoint