高精度集成电压基准源研究.pdf

5.1 本文完成的工作 49 5.2 进一步研究的内容 49 致 谢50 参考文献51 附 录53 原 创 性 声 明54 II 摘 要 本论文研究并设计实现了一种宽电源电压、大负载电流，高稳定性的带隙基 准电路。本文在分析比较各种基准电压源性能的前提下，最终选择了以基于 PTAT(与绝对温度成正比)改进的带隙基准源电路作为设计的基础，并参考了 TL431 的核心结构。为了保证基准电压源的在较宽的电源范围内能输出高精度的 基准电压，本文采用了电源电压分配电路。为了保证电压基准源有大的负载能力， 设计中加增加了输出驱动级电路。另外，本文对启动电路、温度保护电路、过流 和过压保护电路也进行了研究，并设计了优化合理的电路结构。 该电路采用6μm 标准双极型对通隔离工艺实现，并用仿真工具进行了仿真。 结果表明，当电源电压为12V 时，温度范围为-40~85℃时，该电路的温度系数仅 为5.2ppm/℃，启动时间为7.38μs，并在4.5～36V 的电源电压范围内，具有 77.8µV/V 的电源电压调整率以及高达97.21dB 的交流PSRR 和低噪声特性。 关键词：基准电压，温度系数，交流PSRR，电压调整率 I Abstract Abstract AAbbssttrraacctt This paper studied and designed a bandgap voltage reference circuit with wide power supply range, high current and high stability. By comparison of the performance of various voltage references, this paper chose a bandgap voltage reference that based on proportional to absolute temperature (PTAT), the core architecture of TL431 was chosen as a reference circuit. In order to assure the high precision output reference voltage within a wide range of power supply for this circuit, the distribution circuit of power supply was adopted in this paper. Beside the above design, the starting circuit, temperature protection circuit, over current and over voltage circuit was studied as well; the optimal circuit structure was designed also. The circuit was realized via 6μm standard bipolar “opposite-through” isolation process, and the circuit was analyzed by simulation software. The result showed the following: under 12V of power supply and the temperature range of –40~85℃, the temperature