A Robust Bandgap Voltage Reference Using TlnT Compensation Technique for a Low Temperature Coefficient

Precise voltage reference signals are essential for many systems, yet conventional bandgap reference accuracy is limited by higher-order temperature dependencies, particularly the TlnT term. This paper presents a novel approach that directly generates and compensates for the TlnT component by applying a least-squares solution to determine the optimal combination ratios of proportional to absolute temperature (PTAT), complementary proportional to absolute temperature (CTAT), and TlnT voltages, effectively canceling both first- and higher-order temperature effects. Additionally, the constraint of the TlnT generator circuit is mitigated, i.e., the influence of the zero-to-absolute-temperature (ZTAT) current’s temperature coefficient (TCI) on the temperature coefficient of the reference voltage (TCV) using a piecewise compensation technique. An operating point is identified that minimizes process variation. Monte Carlo simulations over a range of process, voltage (1.8–2.5 V), and temperature (–40 to 125 °C) variations demonstrate that the proposed design achieves a TCV as low as 2.39 ppm/°C, maintains an average V<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ref</inf> of 499.19 mV, exhibits a coefficient of variation (CV) of 0.22%, a line sensitivity of 0.0046%/V, and consumes 31.39 μA.