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Why CMOS is called a low power device?

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bala9383

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1. why cmos is called as low power device??

2. why cmos consumes less power??
 

MikeR

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LOW POWER CMOS

CMOS - current source driven by voltage, BJT - current source driven by current. Think over it and you will find the answer.
 

brahma

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Re: LOW POWER CMOS

To be precise for CMOS static power consumption is less...CMOS as u know is a combination of NMOS and PMOS...which governs the vdd and gnd respectively...due to which power is consumed only during transition state..
 

mkh

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LOW POWER CMOS

first of all in mos,power is negligibly consumed in steady state(after switching),compared to say bjt where power is consumed even during ON times as mostly the bjts are not allowed to fully saturate to reduce switching time. Again current thru mos is directly related to width to length ratio of channel.This can be suitably scaled to reduce current, hence power consumption. In CMos the largest contributor to wastege of power is dynamic charging/discharging of mos capacitor.
 

venkat3271

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LOW POWER CMOS

THere will be no direct path between GND and Vdd..
 

A.Anand Srinivasan

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Re: LOW POWER CMOS

venkat3271 said:
THere will be no direct path between GND and Vdd..
how do you say so... even in a simple CMOS inverter there is a direct path between Vdd and Gnd....
As far as i know by reduction in size the power supply rail and hence the power consumption is reduced to form low power CMOS.... please clarify my doubt....
 

electronics_kumar

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LOW POWER CMOS

CMOS is a dynamic power consumer...whereas BJT consumes power always....
 

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