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For the questions below, assume the following device parameters:

K'n=μnCox=200 μA/V², K'p-μpCox-80 μA/V², VLIN|= infinite

Vto,N= |Vto,P|= 0.5V, PHI= |20F|=0.85V for N and P, y=0.3 V0.5, λ=0.1 V-¹/n1) Current Mirror:

a. The simple mirror in Fig. 1(a) is designed with W/L to have gm-0.25mA/V at 20 μA for

the input leg of the mirror with W/L ratio on the output leg 6X larger. If Iref = 20 μA,

calculate the output current for Vout = 0.5, 1.0, and 2.0V.

b. The mirror is updated to be a standard cascode current mirror in Fig. 1(b), using the

same W/L ratios as above for the input leg and output leg. If Iref = 20 µA, calculate the

output current for Vout = 0.5, 1.0, 2.0V.

c. Calculate the output resistance of these two circuits. Using this resistance, estimate

how much the current should change for a 1V change in output voltage change. How

does this compare to your answers in (a) and (b)?

M1

IREF

VDD

Fig. 1(a)

M2

Vout

M1

M3

IREF

VOD

Fig. 1(b)

M2

M4

Vout

Fig: 1

Fig: 2