a question about bandgap ref and non-bandgap ref

hello,

any one know that the bandgap ref and non-bandgap ref, which is used more commonly in industry?

if the bandgap is more common (this is my vague impression, i'm not sure indeed), are there any general drawbacks which are difficult to overcome for the non-bandgap ?

thanks.

bandgap is the circuit which is used to generate the reference voltage....which is compensated by temperature ..using PTAT..non bandgap may not be that accurate to give the constant reference voltage...

bandgap is universal in industry. non bandgap is for research

I find that there are also many non-bandgap reference papers which achive fairly low temperature coefficient. So what is the main consideration for the industry to doubt non-bandgap structure? Does non-bandgap have universal weak points? Is it more deviation caused by PVT or worse psrr or something else?

thanks.

I have one question about bandgap reference, what's the Vmagic's meaning, and in which book i can find this? Thanks!

In analog design, the band gap (or energy gap) is the energy difference between the top of the valence band and the bottom of the conduction band in semiconductors (ie your process).

As you might be aware, for silicon, this is between 1.23-1.26V. In this context, and for the past decades the bandgap reference has been extensively used in order to provide an accurate voltage, by using the difference of two forward-biased diode junctions to generate a PTAT.

In the past couple of years however, many institutions and yes, including universities have forseen a little problem with this approach. As we scale down our technology processes, you will find that so does our supply (ie less than 1.2V). So simply to answer your question, non-bandgap references are recent efforts to resolve a voltage reference below the bandgap of the process.

It is also possible to get the voltage reference below 1.2V using bandgap. A current type bandgap can generate any reference voltage

thank you very much, upstairs!