A Bandgap Reference With Dual High‐Order Compensation Points at Both Low‐ and High‐Temperature Regions

Bandgap reference (BGR) is an important unit circuit to ensure stable power supply. High‐order temperature compensation is a widely adopted technique for improving the accuracy of BGR. However, existing researches about high‐order temperature exhibit their inherent limitations: Single‐point compensation suffers limited temperature accuracy, while piecewise multipoints compensation with superimposed compensation circuits incurs cross‐segment interference, degrading overall compensation accuracy due to out‐of‐interval temperature behavior. In order to overcome the above drawbacks, this paper presents a high‐order compensation circuit capable of simultaneously achieving dual compensation points in both low‐ and high‐temperature regions. The proposed circuit employs a PMOS active differential pair to generate a compensation current by combining a proportional‐to‐absolute‐temperature (PTAT) current with the current–voltage characteristics of an NPN transistor operating in the forward‐active region through a tuning resistor. Using the Lambert function, an explicit relationship for the compensation coefficient is derived, theoretically demonstrating the ability to adjust the tuning resistor to simultaneously achieve both high‐temperature and low‐temperature compensation points, thereby producing a dual high‐order compensation current. A high‐order compensation BGR is constructed on the basis of this circuit. The BGR was designed using SMIC 130‐nm BiCMOS process. Simulation results demonstrate that it achieves a best case temperature coefficient (TC) of 1.8 ppm/°C over the operating temperature range of 40°C–125°C, while providing a reference voltage averaging approximately 1.213 V under a supply voltage of 3.3 V. At 27°C, the circuit exhibits a power supply rejection ratio (PSRR) of 106 dB at 100 Hz and an output line regulation of 0.49 mV/V across a supply voltage range of 2.15–3.75 V, with a maximum power consumption of 81 A. The active area of the BGR is mm.