In the circuit given below the transistor parameters are:

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In the circuit given below the transistor parameters are:
V_TN = 1.7 V and K_n = 0.4 mA/V².
If I_D = 0.8 mA and V_D = 1 V, then value of resistor R_S and R_D are respectively:

1. 2.36 kΩ, 5 kΩ
2. 5 kΩ, 2.36 kΩ
3. 6.43 kΩ, 8.4 kΩ
4. 8.4 kΩ, 6.43 kΩ

Correct Option: A

From figure

I_D =	5 – V_D
	R_D

0.8 × 10^–3 =	5 – 1
	R_D

or R_D =	4	= 5 kΩ
	0·8 × 10^–3

I_D = K_n (V_GS – V_Tn)²
or 0.8 × 10^–3 = 0.4 × 10^–3 (VGS – 1.7)2
or V_GS = √2 + 1.7 = 3.11 V V_G – V_S = 3.11
or V_S = V_G – 3.11 = 0 – 3.11 = – 3.11 V

Again, I_D =	V_S – (–5)	=	–3·11 + 5
	R_S		R_S

or R_S =	1·89	= 2.3625 kΩ
	0·8 × 10^–3