Circuit of 180nm why has the length of all transistors 306nm

[Karandeep]

Circuit of 180nm why has the length of all transistors 360nm

Hello All,

I want to know the technology migration concept . The thing which stuck me is , I m understanding the OP-Amp advanced design for low power . For that I have been through many research articles many of IEEE . as the world is moving towards lower technology . I found many circuits with 180 nm Technology , but the lengths of all the tranisitors are 360 nm. So i want to know that why the author claims that the circuit is 180nm ....

Rather, if the lengths are 360nm the circuit would be on 360nm technology.

So please clarify me :

1. Does the length kept for the transistors decide for technology or anything else?
2. Why the circuits with length 360nm are run at 180nm ...... are those circuits would perform the same at 360 nm also?
3. Whats the keen difference in design at various technologies?

Thanks in advance..................

 

[keith1200rs]

If it is an analog circuit then it is quite likely to not use minimum length transistors - the matching would be terrible. It is often only digital circuitry that will use the minimum width.

Keith

 

[Karandeep]

If it is an analog circuit then it is quite likely to not use minimum length transistors - the matching would be terrible. It is often only digital circuitry that will use the minimum width.

Keith

Thanks Keith ,

But what signifies the technology of analog circuit . See whats my problem is that I have a circuit for ultra low power op-amp . and all the tranistors in it are of 360nm . Now the question arises how do i justify that it is a circuit of 180nm technology.

 

[SP24]

The technology refers to the minimum allowed gate length. So in your circuit there may be 360nm as gate length but there cannot be lengths less than 180nm.

 

[Baas Rietrot]

A 180 nm process refers to the minimum feature size for that process. The rest like the Kn, Kp, Vn, Vp etc. is process
specific, it depends on the manufacturer and how well the process is defined. For this info you need to read the process
datasheet. To do this you will usually sign a nondisclosure agreement.

 

[dick_freebird]

Maybe he used the "I/O" (thick ox) transistors for higher
voltage capability, or more signal range.