level shifter characterization

[sudheerprasad]

do level shifter cell have cell_rise and cell_fall attributes .Iam using a high 2 low level shifter should i measure delay between the 50% voltages even though the voltages are different?
can any one post a level shifter description in .lib file and explain it briefly.

thanx a lot,
sudheer

 

[sudheerprasad]

at least post any site disussing these level shifters