Abstract
Bipolar junction transistors (BJTs) are widely used in high-precision temperature sensors. However, temperature drift caused by the nonlinear curvature of the base-emitter voltage V
BE
, the temperature dependence of the current gain 𝛽, and high-temperature leakage current increases their inaccuracy in wide-temperature-range applications. To address this, this paper systematically reviews the evolution of temperature drift compensation techniques: regarding V
BE
curvature correction, the approach has evolved from piecewise linear compensation to higher-order continuous compensation, with the temperature coefficient (TC) reduced from 6.5 ppm/℃ to below 1 ppm/℃; to address finite-𝛽 effects and associated BJT parameter variations, compensation and calibration techniques have evolved from hardware tuning to digital calibration and active cancellation, progressively improving the reported accuracy; for high-temperature leakage current, the approach has evolved from SOI physical isolation to multi-node active compensation and heater-assisted calibration, enabling accurate operation above 150 ℃. These technological advancements signify that BJT temperature sensors are transitioning from process-dependent to mathematically model-driven designs, and from the analog domain to the mixed-signal domain.