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An NMOS transistor has a threshold voltage (Vth) of 0.4 V and operates at a supply voltage (Vdd) of 1.2 V. A circuit designer is evaluating a proposal to reduce the threshold voltage Vth by 100 mV to obtain faster transistors. (i) By what factor would the saturation current increase (at Vgs = Vds = VDD ) if the transistors were ideal? (ii) By what factor would the subthreshold leakage current increase at room temperature at Vgs = 0 ? Assume n = 1.3 and vT = 26 mV. (Read Section 2.4.4 of your textbook.)

An NMOS transistor has a threshold voltage (Vth) of 0.4 V and operates at a supply voltage (Vdd) of 1.2 V. A circuit designer is evaluating a proposal to reduce the threshold voltage Vth by 100 mV to obtain faster transistors. (i) By what factor would the saturation current increase (at Vgs = Vds = VDD ) if the transistors were ideal? (ii) By what factor would the subthreshold leakage current increase at room temperature at Vgs = 0 ? Assume n = 1.3 and vT = 26 mV. (Read Section 2.4.4 of your textbook.)

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  1. An NMOS transistor has a threshold voltage ( V t h ) of 0.4 V and operates at a supply voltage ( V d d ) of 1.2 V . A circuit designer is evaluating a proposal to reduce the threshold voltage V t h by 100 m V to obtain faster transistors. (i) By what factor would the saturation current increase (at V g s = V d s = V D D ) if the transistors were ideal? (ii) By what factor would the subthreshold leakage current increase at room temperature at V g s = 0 ? Assume n = 1.3 and v T = 26 m V . (Read Section 2.4.4 of your textbook.)

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An nMOS transistor has a threshold voltage of 0.4 V and a supply voltage of VDD = 1.2 V. A circuit designer is evaluating a proposal to reduce VDD by 100 mV to obtain faster transistors. a) By what factor would the saturation current increase (at Vgs = Vds = VDD) if the transistor were ideal? b) By what factor would the subthreshold leakage current increase at room temperature at Vgs = 0? Assume n = 1.4. c) By what factor would the subthreshold leakage current increase at 120 deg C? Assume the threshold voltage is independent of temperature.
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