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Design >> Analog Design >> Compare inverter and OTA in SC-amplifier.
https://designers-guide.org/forum/YaBB.pl?num=1355926750

Message started by Jacki on Dec 19^th, 2012, 6:19am

Title: Compare inverter and OTA in SC-amplifier.
Post by Jacki on Dec 19^th, 2012, 6:19am

Hi,

I have two questions about inverter design. I want to design a SC-amplifier by using inverter to replace OTA.
First is how to calculate the power consumption of inverter? Is it the same way as we calculate the digital power consumption?
P=(1/2)*VDD(square)*fs*CL
fs is sampling frequency, CL is the load.

Second is for SC-amplifier based on OTA, gain bandwidth product of OTA is important for settling. Is it the same for inverter, if I use inverter instead of OTA. Do they have the same spec. for gain bandwidth product?

If somebody have good references for inverter design, could you please introduce to me.

Thank you.

Jacki.

Title: Re: Compare inverter and OTA in SC-amplifier.
Post by boe on Dec 20^th, 2012, 5:34am

Jacki,

Jacki wrote on Dec 19^th, 2012, 6:19am:

... [H]ow to calculate the power consumption of inverter? Is it the same way as we calculate the digital power consumption?
P=(1/2)*VDD(square)*fs*CL

No. the digital power formula just gives you the power needed to recharge the load cap.

- B O E

Title: Re: Compare inverter and OTA in SC-amplifier.
Post by Jacki on Dec 20^th, 2012, 6:35am

Hi boe,

Thank you. Now I use iprobe and calculator in spectre to get the average current, then I think I can use this value to estimate the power consumption.

Jacki.