In an NMOS current mirror, the two transistors 21 and Q2 have equal channel lengths but...

  

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In an NMOS current mirror, the two transistors 21 and Q2 have equal channel lengths but Q2 has three times the width of Q₁. The input side of the mirror, Q1, is connected to the power supply VDD 1.3 V through a resistance R. The mirror is required to provide in the drain of Q2 a current Io whose nominal value, obtained at Vo = VGS, is 240 μA. The minimum permitted output volt- age is 0.3 V but the output voltage can be as high as VDD. Over this range of output voltage, the change in Io is to be limited to 10% of the nom- inal value. Find the required value of R and the dimensions of the two transistors. The MOSFETs are specified to have Vin = 0.4 V, V = 10 V/μm, and nCox = 0.5 mA/V² In an NMOS current mirror, the two transistors 21 and Q2 have equal channel lengths but Q2 has three times the width of Q₁. The input side of the mirror, Q1, is connected to the power supply VDD 1.3 V through a resistance R. The mirror is required to provide in the drain of Q2 a current Io whose nominal value, obtained at Vo = VGS, is 240 μA. The minimum permitted output volt- age is 0.3 V but the output voltage can be as high as VDD. Over this range of output voltage, the change in Io is to be limited to 10% of the nom- inal value. Find the required value of R and the dimensions of the two transistors. The MOSFETs are specified to have Vin = 0.4 V, V = 10 V/μm, and nCox = 0.5 mA/V²