temperature sensing circuits

[KaiZX]

I'm trying to add an additional voltage output to a bandgap reference to output a PTAT voltage referenced to GND that can provide information on the temperature of the circuit. In other words, to provide a voltage whose slope = voltage/degree C. This output voltage will will need to be both Vdd and process independent. My idea is to take the PTAT current out of the PTAT block of the bandgap and use that somehow.

Does anyone have suggestions as to how I can best do this? Or can provide references?

 

[elbadry]

Simply get PTAT current ( VT ln(m)/R ) and dump it into a resistor using a high quality cascode current mirror.

You will thus get a voltage VT ln(m)*R'/R. If you use matched resistors, this should be highly PVT insensitive

I believe there are papers on better ways of doing this

 

[KaiZX]

Can you point out as to where I can find these papers?

 

[brahmanlar]

https://www.new-wave-concepts.com/files/cw11d_pr.exe

I think you can find it examples of this program

"Circuit Wizard Demonstration" find this program and get examples...

You'll like it so much........