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

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.