Voltage Reference With Linear-Temperature-Dependent Power Consumption
Haoyu Zhuang, Xiaoxian Liu, Hao Wang
Abstract
This article presents a novel pico-watt voltage reference (VR) circuit whose power consumption is well controlled at high temperature. Unlike a traditional pico-watt VR circuit whose power consumption increases exponentially with temperature, the power consumption in this article increases linearly with temperature, thus saving much energy at high temperature. It generates the reference voltage through a 2-transistor (2-T) structure and a current generator to well control the current versus temperature. In the current generator, a gate leakage transistor replaces a huge resistor, thus saving 4-mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> area. Fabricated in a 0.13- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> CMOS process, this VR circuit generates a reference voltage of about 560 mV and shows an average temperature coefficient (TC) of 18.4 ppm/°C after trimming across −25 °C to 85 °C and a line sensitivity (LS) of 0.15%/V, while consuming 20 pW at 1-V <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V} _{\text {DD}}$ </tex-math></inline-formula> and 27 °C. The power consumption at 3.3-V <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V} _{\text {DD}}$ </tex-math></inline-formula> and 85 °C is 114 pW, which is at least two times smaller than reported in state-of-the-art work at high temperature. The core area is 0.003 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .