Page 965 - Basic Electrical Engineering
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Figure 14.10 (a) Approximate V–I characteristics; (b) equivalent circuit


               Example 14.1    A silicon diode is connected across a 3 V supply with a
               series resistance of 20 Ω. Neglecting diode resistance, calculate the diode

               current.


               Solution:


















                                                         Figure 14.11

               A silicon diode has V  = 0.7 V. The diode equivalent circuit has been shown.
                                         F
               Applying Kirchhoff’s voltage law,

                                                + 3 V – 20 I – 0.7 V = 0



                or,                    20 I = 3 – 0.7 = 2.3 V


                                            I =     = 0.115 A
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