Answer Happy

Exercise: Critical points of diode current-voltage characteristics. The I–V characteristics of diodes are frequently characterized in terms of four critical points, namely forward voltage one, VA forward voltage two, V forward voltage three. Vs, and reverse saturation current, Is, specified at the operating current (e.g. 100 mA), a small forward current (e.g. 10 uA), a very small forward current (e.g. 1 HA), and at negative bias (e.g.-5 V), respectively. The critical points are shown in Fig. 4.6. (a) Explain the relevance of the critical points. (b) Two GaInN diodes have the following data: (1) Va = 3.2 V, Vo = 2.5 V, V3 = 2.3 V. Is = 0.8 uA; (2) Va = 3.4 V, Vo = 2.0 V, V3 = 1.8 V, 1s = 0.8 A. Which device has the more favorable characteristics?
100 mA 1 10 μΑ- 1 μΑ Fig. 4.6. Critical points of diode I-V characteristic, namely "forward voltage une", Vil (measured at operat- ing current, e.g. 100 mA), "forward voltage two", V2 (measured at low current, c.g. 10 MA), "forward voltage three". Vr (measured at very low current, e.g. 1A), and reverse satura- tion current measured at e.g. - 5.0 V). V 1 Yo V2 VEL