Thank you. Please tell the attached derivation is correct?This is the well-known Banba voltage reference. If you want to study it read its paper (https://ieeexplore.ieee.org/document/760378)
I don't know what you mean with folded in this circuit. This is considered a "sub-bandgap voltage reference" since it is below the usual 1.25V bandgap voltage. Because of that, it can also operate at power supplies <1V (which can be considered "low voltage").Is it a low voltage folded bandgap reference circuit.
The short version of expression is that you add a PTAT current to a CTAT current to get a zero to absolute temperature (ZAT) current.Thank you. the attached paper is useful. Is it a low voltage folded bandgap reference circuit.
Is the derivation of vbgt is correct?
Thanks very much for the detailed description. I study it and if needed further I will discusses.The short version of expression is that you add a PTAT current to a CTAT current to get a zero to absolute temperature (ZAT) current.
PTAT comes from \[\Delta\] VEB /R1 = VT ln / R1.
CTAT voltage VEB is divided by (R2 + (R4||R5) to give a CTAT current.
Both currents are added in IMP4 (ZTAT current).
IMP4 is copied into IMP6 and flows in R3 to produce a ZTAT output voltage as given by the expression you have derived.