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MOSFETs
• Physical structure and operation of the MOS field-effect transistor
• Current-voltage characteristics for MOSFETs
• Using MOSFETs for logic gates
• Metal Oxide Semiconductor Field Effect Transistor
Overview
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MOSFETs
Device Structure and Physical Operation
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MOSFETs
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MOSFETs
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MOSFETs
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MOSFETs
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MOSFETs
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MOSFETs
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MOSFETs
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MOSFETs
Consider a process technology for which Lmin = 0.4 μA, tox = 8 nm, μn = 450 cm2/V-s, and Vt = 0.7V. Find Cox and kn’. For a MOSFET with W/L = 8 μm / 0.8 μm, calculate the values of VOV, VGS, and VDSmin needed to operate the transistor in the saturation region with a dc current ID = 100 μA. For the device found above find the values of VOV and VGS required to cause the device to operate as a 1000-Ω resistor for a very small VDS.
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MOSFETs
Consider a process technology for which Lmin = 0.4 μA, tox = 8 nm, μn = 450 cm2/V-s, and Vt = 0.7V. Find Cox and kn’. For a MOSFET with W/L = 8 μm / 0.8 μm, calculate the values of VOV, VGS, and VDSmin needed to operate the transistor in the saturation region with a dc current ID = 100 μA. For the device found above find the values of VOV and VGS required to cause the device to operate as a 1000-Ω resistor for a very small VDS.
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MOSFETs
Consider a process technology for which Lmin = 0.4 μA, tox = 8 nm, μn = 450 cm2/V-s, and Vt = 0.7V. Find Cox and kn’. For a MOSFET with W/L = 8 μm / 0.8 μm, calculate the values of VOV, VGS, and VDSmin needed to operate the transistor in the saturation region with a dc current ID = 100 μA. For the device found above find the values of VOV and VGS required to cause the device to operate as a 1000-Ω resistor for a very small VDS.
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MOSFETs
Current-Voltage Characteristic
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MOSFETs
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MOSFETs
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MOSFETs
2.5V
1.5V
Assume VTN = 0.5 V, kpn = 230 μA/V2
Assume W = 3 μm and L = 0.25 μm
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MOSFETs
0.6V
0.4V
Assume VTN = 0.5 V, kpn = 230 μA/V2
Assume W = 3 μm and L = 0.5 μm
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MOSFETs
100 mV
2.5V
Assume VTN = 0.5 V, kpn = 230 μA/V2
Assume W = 1 μm and L = 10 μm
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MOSFETs
1.5 V
2.5V
Assume VTN = 0.5 V, kpn = 230 μA/V2
Assume W = 1 μm and L = 10 μm
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MOSFETs
Drive an LED
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MOSFETs
What about PFETs?
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MOSFETs
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MOSFETs
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MOSFETs
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MOSFETs
Logic GatesInverter
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MOSFETs
Logic Gates2 input NAND
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MOSFETs
Logic Gates2 input NOR
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MOSFETs
Logic Gates
F AB CD
