A bandgap reference source for Buck-type DC-DC regulators

To address the reference voltage issue in Buck-type DC-DC voltage regulators, a bandgap reference source suitable for Buck-type DC-DC regulators is designed based on the 0.18μm BCD process from Dongbu HiTek. Building on the analysis of traditional bandgap reference sources, a pre-regulation module is added to broaden the input voltage range and improve the power supply rejection ratio. An output buffer stage is also incorporated to enhance the driving capability of the circuit, effectively ensuring the stability of the output reference voltage. Additionally, an over-temperature protection feature is included to provide safety for the circuit. The circuit has been simulated, and its functionality has been validated. The circuit has passed multiple process tape-out tests and exhibits good robustness, making it suitable for various Buck-type DC-DC regulator chips.