Determine the range of input voltage that maintains the output voltage of 10 V, for the regulator circuit shown.

Question

Accepted Answer

As [latex]V_{o}[/latex] = 10 V constant and [latex]R_{L}[/latex] = 10 kΩ constant,
we have

[latex]I_{L} =\frac{V_{o}}{R_{L}}=\frac{10}{10 × 10^{3}}[/latex] = 1 mA

When [latex]V_{in} = V_{in (max)}. I_{Z} = I_{Z max}[/latex]
Now I = [latex]I_{Z} + I_{L}[/latex]
Therefore, [latex]I_{max} = I_{Zmax} + I_{L}[/latex] = 24 mA + 1 mA = 2 mA.

[latex]\frac{V_{in(max)} – V_{Z}}{R}[/latex] = 25 mA

Therefore, [latex]V_{in(max)} –10 = 1 × 10^{3}(25 × 10^{– 3})[/latex]
[latex]V_{in(max)}[/latex] = 35 V.
When [latex]V_{in} = V_{in(min)}, I_{Z} = I_{Zmin}[/latex] = 5 mA
Therefore, [latex]I_{min} = I_{Zmin} + I_{L}[/latex] = 5 mA + 1 mA = 6 mA

[latex]\frac{V_{in (min)} – V_{z}}{R} = 6 × 10^{–3}[/latex]

[latex]V_{in(min)} –10 = 1 × 10^{3}(6 × 10^{– 3})[/latex]
[latex]V_{in(min)}[/latex] = 16 V
Thus range of input voltage is 16 V to 35 V for which the output voltage will be of 10 V.

Question 18.38: Determine the range of input voltage that maintains the outp...

Related Answered Questions