A 0.81–1.46 ppm/∘C High-Order Segmented Curvature-Compensation Bandgap Reference with Dynamic Element Matching Offset Cancellation for a Battery Management System

A precise high-order segmented curvature-compensation bandgap reference (BGR) with dynamic element matching (DEM) offset cancellation has been developed. The proposed segmented curvature-compensation scheme with a resistive trimming network is used to reduce the errors caused by the nonlinear dependence of the bipolar transistor base-emitter voltage (VBE) on temperature. To decrease the std dev (σ) of the reference voltage (VREF), DEM technology is applied in the core BGR to alleviate the current branch mismatch, as well as the current mirror mismatch in the error amplifier. The proposed BGR circuit is designed on a 0.18 μm BCD process with an active area of 300×375μm and 61.5 μA@5 V current consumption in the bandgap core circuit. The post-simulation results show that the proposed BGR achieves a temperature coefficient (TC) of 0.81–1.46 ppm/°C from −40 °C to 125 °C and a 0.045% σ/μ variation on a 3.2768 V VREF.