A PVT-Insensitive Sub-Ranging Current Reference Achieving 11.4-ppm/°C From -20°C to 125°C

This article presents a sub-ranging current reference with a low-temperature coefficient (TC) across a wide temperature range. By using a TC-adjustable current source and a process-insensitive sub-range detector, the impact of second-order TC can be reduced by nearly fourfold, without any discontinuities at the subrange boundaries. Implemented in a 0.18-μ m CMOS process, the proposed current reference achieves an average TC of 11.4-ppm/°C across from -20 °C to 125 °C, obtained from 45 samples across five process corners without chip-by-chip calibration. The proposed current source exhibits low line and load sensitivities of 365 and 181 ppm/V, respectively, and an integrated noise of 38.9 pArms within a 10-Hz bandwidth.