Design of a Low Temperature Drift On-Chip Power Supply Module Circuit with Nonlinear Temperature Curvature Compensation

Low-dropout regulators (LDOs) are an important part of power management integrated circuits (PMICs). Due to the IC chip’s heat generation and ambient temperature changes, etc., the chip is usually operated at changing temperatures, which requires the LDO to ensure output voltage consistency over a wide temperature range. As the LDO output voltage reference source, in order to get smaller reference voltage variation with the temperature change, bandgap reference needs to eliminate the non-linear relationship between output voltage and temperature. Additionally, the bandgap reference should also have a high power supply rejection ratio. In this paper, a compensation circuit is developed for bandgap reference based on a transconductance amplifier with a high power supply rejection ratio, and a nonlinear temperature drift compensation current is generated and injected. As a result, the insensitivity of the bandgap reference voltage to the temperature is significantly improved by injecting this compensation current into the low-current-density terminal transistor of the bandgap reference, and a temperature coefficient of 2.733ppm/°C is realized. Based on this, an LDO power supply module is designed, which is proven to have good performance by simulation, and can be used as the internal power supply module of PMIC.