What is meant by HVT & SVT cells in library?

[kumar_eee]

What is meant by HVT & SVT cells in library?.. which one is better?..

 

[sekapr]

what does hvt cell stand for

HVT , LVT stands for high threshold and low threshold transistor cells. This is used for leakage power optimization

 

[eternal_nan]

svt lvt hvt

To elaborate a bit, processes that support multi-Vt have more than one Vt adjustement processing step (Vt adjustment is done by ion implantation into the transistor channel region), so for high-Vt you implant few ions, for standard a bit more, for low - the most ions.

 

[shelkerahul]

how are hvt transistors made

For timing critical path low Vt cell is better, but at cost of more leakage power.
For non timing critical path High Vt cell is good choice

 

[WzWzWz]

svt hvt lvt cpk

hvt: low leakage power library. for low power use but low critical timing.
Svt: middle leakage power library. normal use
lvt: big leakage power library. timing critical path used.

 

[zhipeng]

What is typical leakage reduction by replacing RVT cells with HVT, for a deep sub-micron process?

Looking at the databooks of a 45nm std cell library, it seems cell leakage power of HVT is almost as 1/2 as of RVT. Even if I replace all cells by HVT, the leakage only get reduced by 1/2. Is that normal?

 

[gourav.panda]

Re: what does hvt cell stand for

HVT is High threshold voltage. i.e the leakage power is less for High threshold voltage cells. but for SVT cells the leakage power is more and faster too..

 

[jeet_asic]

Re: how are hvt transistors made

why does lower vt cells have more leakage as compared to higher vt cells ?

For timing critical path low Vt cell is better, but at cost of more leakage power.
For non timing critical path High Vt cell is good choice

 

[birdy123]

Please have a look in below post

https://vlsiquestion.blogspot.in/2010/09/high-and-low-vt-cells-and-5-important.html