JSSC 2021第10期Analog Circuits0.18μm CMOSBandgap Reference

A Single BJT Bandgap Reference With Frequency Compensation Exploiting

提出一种单BJT带隙基准源，通过频率补偿优化稳定性和功耗

温度系数26.3 ppm/°C(-40°C~140°C)，电压精度0.33%，PSR -52dB@100Hz/-44dB@1MHz，功耗192nW

带隙基准源单BJT频率补偿低功耗温度稳定性

▸创新点1：单BJT分支设计（电路创新） - 通过仅使用单个BJT分支替代传统多BJT结构，显著减少了元件数量和芯片面积，同时降低了功耗（192 nW），实现了更紧凑的布局（0.0082 mm²）。

▸创新点2：PTAT嵌入式放大器（系统创新） - 将PTAT电流生成功能集成到放大器设计中，简化了温度补偿架构，避免了传统方案中额外的PTAT生成电路，提升了温度稳定性（26.3 ppm/°C）。

▸创新点3：优化的频率补偿方案（方法创新） - 通过将补偿电容连接至PTAT放大器的电流镜像节点，动态调节镜像极点位置，在保证相位裕度的同时降低补偿电容值，实现-52 dB@100Hz的PSR性能。

▸创新点4：复合性能优化（系统创新） - 通过协同设计单BJT架构与频率补偿方案，在-40°C~140°C范围内同时达成低温度系数、高电源抑制比和亚微瓦级功耗，突破传统BGR的功耗-精度折衷限制。

Abstract

In this article, we propose a bandgap reference (BGR) with a single bipolar junction transistor (BJT) branch and a proportional-to-absolute-temperature (PTAT)- embedded ampliﬁer. Having fewer BJT and passive components, the proposed BGR uses less power and area compared to the conventional BGR that uses multiple BJTs and resistors. As the proposed BGR achieves temperature compensation by employing a feedback loop that has two gain stages, frequency compensation is required. We propose frequency compensation scheme where a compensation capacitor is connected between the BGR output and a current mirror node in the PTAT-embedded ampliﬁer. By using this scheme, location of a mirror pole associated with the current mirror node can be optimized to achieve both improved stability and low power consumption. Fabricated in 0.18- μm CMOS, the proposed BGR achieves temperature coefﬁcient of 26.3 ppm/ ◦C over −40 ◦C–140 ◦C; voltage accuracy (σ/μ) of 0.33%; and power supply rejection (PSR) of −52 dB, −44 dB at 100 Hz, 1 MHz respectively; while occupying 0.0082 mm2 and consuming 192 nW without startup circuit and trimming.