Nano-Ampere Area-Efficient Current Reference Based on Temperature-Controlled Pseudo-Resistor

This paper proposes a CMOS current reference circuit that avoids the use of huge area resistors. In order to achieve an independent-of-absolute-temperature (IOAT) current, proportional-to-absolute-temperature (PTAT) and complementary-to-absolute-temperature (CTAT) voltages are respectively applied to the drain and gate terminals of a n-MOS pseudo-resistor. The circuit was carried out using a 180 nm CMOS process. Extensive post-layout simulation results in Spectre show that the proposed topology presents a current consumption of 6.30 nA (typical), a temperature coefficient (TC) of 219 ppm/°C in a range from −40 to 120 °C, and a line regulation (LR) of 12.08 %. The proposed current reference occupies a silicon area of 0.0018 mm2.