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Scaling laws
Scaling Laws in VLSI Design Scaling laws play a crucial role in the design and optimization of microchips and integrated circuits. These laws dictate the re...
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Scaling Laws in VLSI Design Scaling laws play a crucial role in the design and optimization of microchips and integrated circuits. These laws dictate the re...
Scaling Laws in VLSI Design
Scaling laws play a crucial role in the design and optimization of microchips and integrated circuits. These laws dictate the relationship between various dimensions and characteristics of electronic components on a chip, such as transistors, capacitors, and resistors.
Channel Length:
The channel length is the physical distance between two adjacent points on a transistor or gate. Due to the lithography process, channel length is typically measured in nanometers (nm).
Supply Voltage (Vcc):
Vcc is the voltage applied to the collector (source) and the drain (gate) terminals of a transistor. Increasing Vcc increases the charge carrier density in the channel, leading to increased current and power dissipation.
Gate Voltage (Vgs):
Vgs is the voltage applied to the gate terminal relative to the source. Changes in Vgs affect the charge carrier injection and extraction processes, which in turn influence the current flow.
Capacitance:
Capacitance represents the ability of a circuit to store electrical charge. Since chip dimensions are reduced through scaling, the capacitance of each component needs to be considered.
Resistance:
Resistance measures the opposition to current flow in a circuit. As the channel length and gate voltage are scaled down, the resistance of the channel increases, while the resistance of the transistor remains relatively constant.
Scaling Laws:
Leibniz's Law: This law relates the minimum channel length to the gate-source voltage and the supply voltage.
Child's Law: This law states that the drain current is proportional to the square of the channel length.
Hodgan-Talkeby Law: This law relates the mobility of charge carriers to the channel length and the gate voltage.
Examples:
In CMOS logic, the channel length is typically 10 nm, and the gate voltage is typically 0.7 V.
In integrated circuits, capacitors are typically designed with smaller dimensions to maintain high density and low capacitance.
Scaling laws are used in VLSI design to optimize device performance and achieve smaller chip sizes