In the circuit given below the transistor parameters are

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In the circuit given below the transistor parameters are
V_TN = 1 V, and k_n = 36 µA/V². If I_D = 0.5 mA, V₁ = 5 V and V₂ = 2 V then the width-to-length ratio
i.e. W required in each transistor is
L

W W W
L ₁ L ₂ L ₃

1. 1.75, 6.94, 27.8
2. 4.93, 10.56, 50.43
3. 35.4, 22.4, 8.53
4. 56.4, 38.21, 12.56

Correct Option: A

For each transistor M₁, M₂ and M₂
V_GS = V_DS i.e. V_DS > V_GS – V_TN
Therefore all the transistor are in saturation Given that
V_TN = 1 V
k′_n = 36 µA/V²
I_D = 0.5 mA
V₁ = 5 V_S V₂ = 2 V
For transistor M₃
V₂ = 2V = V_GS₃
I_D = 0.5 × 10^–3

=	1	36 × 10^–6		W			. (2 – 1)²
	2			L		₃

after simplifying we get		W			= 27.8
		L		₃

For transistor M₂,
V_GS₂ = V₁ – V₂ = 5 – 2 = 3 V
I_D = 0.5 × 10^–3

= 36 × 10^–6		W			(3 – 1)²
		L		₂

or		W			= 6.94
		L		₂

For transistor M₁
V_{GS₁ = 10 – V₁ = 10 – 5 = 5 V
I_D = 0.5 × 10^–3
= 1 36 × 10^–6 W . (5 – 1)²
2 L ₁

or W = 1.74
L ₁

Hence alternative (A) is the correct choice.}