A Novel Sub-1V Bandgap Reference with 17.1 ppm/0C Temperature coefficient in 28nm CMOS

Traditional Banba bandgap is very popular in deep sub-micron CMOS technologies because of its sub 1V output nature. But unfortunately, it won’t provide PTAT nature current and has several operating points, unlike two in the voltage mode BGR. This work analyzes the Banba circuit in a detailed way so that it’s easy to demonstrate multiple stable operating and lists some of its other shortfalls. This paper presents a novel sub-1V bandgap architecture, which can provide PTAT current and sub-1V output without having multiple operating points. A modified self-bias opamp has been proposed to minimize the systematic offset and its temperature drift. A prototype was developed in 28nm TSMC CMOS technology and post-layout simulation results were performed. Proposed BGR targeted at 500mV works from 1V supply without having any degradation in the performance while keeping the integrated noise of $18.2 \mu \text{V}$ and accuracy of $17.1ppm/^{\mathbf{0}}C$, while the traditional Banba was resulting $23.4ppm/^{\mathbf{0}}C$. Further, the circuit consumes ($29.8 \mu \text{W}$) of power and occupies $71*(39 \mu \text{m})^{\mathbf{2}}$silicon area.