Sub-1V bandgap reference design using TSMC 180nm BCD process

Abstract

This paper presents the design and simulation of a sub-1V bandgap reference (BGR) circuit implemented using the TSMC 180 nm BCD high-voltage process (T18HVG2). The proposed circuit delivers a stable 0.8 V output reference voltage with minimal sensitivity to variations in process, supply voltage, and temperature (PVT), making it well-suited for integration in low-voltage power management systems such as DC-DC converters. The design incorporates a curvature-compensated architecture and a fully integrated two-stage operational amplifier with startup and bias circuitry to ensure robust operation across a wide temperature range from –40 °C to +125 °C. The complete BGR occupies an active area of 0.04327 mm² and consumes a maximum of 36.17 µA at 5 V supply in the worst-case corner. Simulations demonstrate a temperature coefficient of 65 ppm/°C and line regulation of 1.17 mV/V (0.145 %/V), with DC PSRR of −47 dB at low frequencies. While not optimized for ultra-low power or ultrahigh accuracy, the design achieves a favorable balance of performance, layout efficiency, and a wide input voltage range, making it a practical choice for certain mixed-signal and power management applications in 180 nm BCD technologies.