Can low voltage process improve the speed?

[SherlockBenedict]

I read somewhere that by going into lower voltages in CMOS technology, the speed of the circuit will also gets increased. Can you tell me why?

Thanks

 

[Ow@i$]

Not sure maybe because high voltages heat up the device which effects the functionality/Frequency !!!

 

[erikl]

I read somewhere that by going into lower voltages in CMOS technology, the speed of the circuit will also gets increased. Can you tell me why?

There's always an RC slew rate δV/δt limitation. Lower δV --> lower δt .

Same reason is one of the motivations for LVDS usage.

 

[SherlockBenedict]

There's always an RC slew rate δV/δt limitation. Lower δV --> lower δt .

Same reason is one of the motivations for LVDS usage.

Hello erikl,

Thanks for the reply but I don't get it. What do you mean by δV/δt limitation? Are you talking about the RC response of a circuit? If that is the case then both higher and lower voltages has the same time constant τ as it depends only on the RC values and hence the time taken to settle to some particular fraction of the final voltage should be same for both the cases right?

 

[erikl]

Hello Benedict T.C. C. aka Sherlock Holmes ;-)

Right, I shouldn't have led you to the RC path. The δV/δt limitation stems from the current limitation of an amp stage, which produces a (more or less) constant current into a capacitive load, in most cases this is the last (output) stage of an amp. In such case my above statement should apply.

Cheers, erikl

 

[SherlockBenedict]

Oh got it. You were talking about the slew rate. Thanks

 

[erikl]

Oh got it. You were talking about the slew rate. Thanks

Sure, as stated in my very first answer above ;-)