What are the effects of using low Vt devices?

[Resistance]

Effects of low Vt..

Hi,

I want to know all the efects of using low Vt devices.. Y specifically Dual vt devices are preferred ..

explain.

regards

 

[anjali]

Re: Effects of low Vt..

less noise margin

 

[johnz]

Re: Effects of low Vt..

0.13um technology and technology under 0.13um have bigger percentage of leakage power. multiple Vt std library( low, normal, high Vt) are used for reducing leakage power .

They have same area.

low Vt ( fast, bigger leakage) , high Vt ( slow, smaller leakage)

 

[silencer3]

Effects of low Vt..

i agree with johnz.

below 0.13um or even at 0.13um, leakage power is a significant thing to consider as it is not just about power but also about timing, thermal, noise..etc.

now a days it is better to first synthesize design using HIGH Vt library and replace the timing critical paths with LOW Vt cells to meet timings. This ensures a better power design with required speed.

 

[Nimer]

Re: Effects of low Vt..

hi

sorry for the intrusion, but wht is Vt ???

 

[manu_leo]

Re: Effects of low Vt..

Vt is threshold voltage for CMOS. Low Vt cause more leakage

 

[elecs_gene]

Re: Effects of low Vt..

hi guys
which one has higher power dissipation-low or high Vt????could u explain in detail..
could u compare the leakage,static and dynamic dissipation in all these ???

regards

 

[electronics_kumar]

Re: Effects of low Vt..

low Vt will have less power dissipation whereas high Vt will have more power dissipation

 

[Nandy]

Effects of low Vt..

One interesting thing is, the dynamic power consumption (running time) maybe no difference between low/high VT. The reason is High VT is slower and has longer transition time which uses more power.

Nandy
www.nandigits.com
Netlist Debug/ECO in GUI mode.

 

[Resistance]

Re: Effects of low Vt..

hi ,

Now can any of u explain clearly wat makes a low vt device fast and dissipate more power... then which factor changes :

Static or Leakage????
Tell me rules of thumb how they differ.

Elaborate answer please


regards

Added after 1 minutes:

hi anjali,

Wat does Dual Vt got to dom with noise margin..

please elaborate

 

[erich123]

Re: Effects of low Vt..

=============================================
One interesting thing is, the dynamic power consumption (running time) maybe no difference between low/high VT. The reason is High VT is slower and has longer transition time which uses more power.

Nandy
==============================================

Hi Handy,

You words sounds reasonable, but I don't think your explaination is right, we use High VT mainly for leakage reduction, it is not dynamic power. What do you think?