Electronic Circuits with MATLAB, PSpice, and Smith Chart

2Diode Circuits

Chapter Outline

1. 2.1 The v‐i Characteristic of Diodes
   1. 2.1.1 Large‐Signal Diode Model for Switching Operations
   2. 2.1.2 Small‐Signal Diode Model for Amplifying Operations
2. 2.2 Analysis/Simulation of Diode Circuits
   1. 2.2.1 Examples of Diode Circuits
   2. 2.2.2 Clipper/Clamper Circuits
   3. 2.2.3 Half‐wave Rectifier
   4. 2.2.4 Half‐wave Rectifier with Capacitor – Peak Rectifier
   5. 2.2.5 Full‐wave Rectifier
   6. 2.2.6 Full‐wave Rectifier with LC Filter
   7. 2.2.7 Precision Rectifiers
   8. 2.2.8 Small‐Signal (AC) Analysis of Diode Circuits
3. 2.3 Zender Diodes
4. Problems

2.1 The v‐i Characteristic of Diodes

Figure 2.1(a) shows the symbol for a diode, which allows an electric current (as a low resistance) in the forward direction, while blocking current (as a large resistance) in the reverse direction. Figure 2.1(b) shows the v‐i characteristic of a practical diode, which can be approximated by the Shockley diode equation (named after transistor coinventor William Bradford Shockley) or the diode law:

(2.1.1a,b)

Figure 2.1 Symbol and v‐i characteristic of a diode.

where I_S, η, and V_T are the leakage (reverse saturation) current, the empirical constant (called the emission coefficient or ideality factor) between 1 and 2, and the thermal voltage, respectively.

Note that the thermal voltage V_T is ...