contestada

D 4.37. Assuming the availability of diodes for which vD = 0.75 V at iD = 1mA, design a circuit that utilizes four diodes connected in series, in series with a resistor R connected to a 15-V power supply. The voltage across the string of diodes is to be 3.3 V.

Respuesta :

Answer:

R = 0.5825 k ohm

Explanation:

given data

vD = 0.75 V

iD = 1mA

resistor R = 15-V

solution

we get here first vD that is

vD = [tex]\frac{3.3}{4}[/tex]  

vD = 0.825

so

iD = Ise × [tex]e^{\frac{vD}{nvT}}[/tex]      

n = 1

so we can say

[tex]\frac{iD2}{iD1} = e^{\frac{vD2-vD1}{nvT}}[/tex]  

so it will

iD2 = iD1 × [tex]e^{\frac{vD2-vD1}{nvT}}[/tex]

put here value and we get

iD2 = 1 × [tex]e^{\frac{0.825-0.75}{25}}[/tex]  

iD2 = 1 × [tex]e^{3}[/tex]  

iD2 = 20.086 mA

so

R will be

R = [tex]\frac{15-3.3}{ID}[/tex]  

R = 0.5825 k ohm

Otras preguntas