If the ratio isW = 40 andW = 15, then V0 is:L1L2

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Direction: Consider the circuit shown below:
The both transistor have parameter as follows:
V_TN = 0.8 V, k_n = 30 ΩA/V²

If the ratio is W = 40 and W = 15, then V₀ is:
L ₁ L ₂

1. 2.91 V
2. 2.09 V
3. 3.41 V
4. 1.59 V

Correct Option: A

According to question

	W			= 40 and		W			= 15
	L		₁			L		₂

Again
K_n₁ (V_GS₁ – V_TN₁ )2=K_n₂ (V_GS₂ – V_TN₂ )2
40 (V_GS₁ – 0.8)2 = 15 (V_GS₂ – 0.8)2 `…(A)
V_GS₁ + V_GS₂ = 5 …(B)
from (A) and (B)
40 (V_GS₁ – 0.8)2 = 15 (5 – V_GS₁ – 0.8)2
8 [V²_GS₁ +.64 –1.6 V_GS₁] = 3 [17.64 + V²_GS₁ –8 V_GS₁]
5 V²_GS₁ + 11.2 V_GS₁ – 47.8 = 0
V_GS₁ = 2.09
V₀ = 5 – V_GS₁
= 5 – 2.09 = 2.91 V