Ultra-Low-Power Sub-1 V 29 ppm/°C Voltage Reference and Shared-Resistive Current Reference

Abstract

This paper presents a curvature-compensated sub-1V voltage reference (VR) and a shared-resistive nanoampere current reference (CR) in a 130nm CMOS process. The CR is used to generate a bipolar junction transistor complementary-to-absolute-temperature voltage, which is summed up with a proportional-to-absolute-temperature voltage generated using a summing network of PMOS gate-coupled pairs. The measured output voltage and current references from 10 chips ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\mathrm {REF}}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$I_{\mathrm {REF}}$ </tex-math></inline-formula> ) at room temperature are 469mV and 1.86nA, respectively. The measured average temperature coefficient of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\mathrm {REF}}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$I_{\mathrm {REF}}$ </tex-math></inline-formula> are 29ppm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$/^{\circ} \text{C}$ </tex-math></inline-formula> and 822ppm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$/^{\circ} \text{C}$ </tex-math></inline-formula> over a temperature range from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$- 40^{\circ} \text{C}$ </tex-math></inline-formula> to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$120^{\circ} \text{C}$ </tex-math></inline-formula> . The minimum supply voltage of the voltage-current reference is 0.95V, and the total power consumption is 30nW.