A 1-V Bandgap Reference in 7-nm FinFET With a Programmable Temperature Coefficient and Inaccuracy of ±0.2% From −45°C to 125°C

Abstract

We present a 1-V precision voltage reference with a programmable temperature coefficient (“ temp-co ”). The voltage reference is based on a parasitic bipolar junction transistor (BJT) realized within the process steps available in the chosen 7-nm FinFET technology. Details of its characterization and SPICE modeling are presented to provide insight into key device–circuit optimization choices. The trimming techniques needed to cope with process spread together with two curvature compensation techniques are presented. The reference achieves a maximum inaccuracy of ±0.2% and a minimum temp-co of 6 ppm/°C from −45°C to 125°C. Furthermore, its temp-co is digitally programmable between −7 mV/100°C and +8 mV/100°C. Its line regulation is 0.1%/V, and it occupies 0.078 mm2.