一种用于音频Σ-ΔA/D转换器的CMOS带隙电压基准源

摘要

在传统带隙基准电压源电路结构的基础上,通过在运放中引入增益提高级,实现了一种用于音频Σ-ΔA/D转换器的CMOS带隙电压基准源。在一阶温度补偿下实现了较高的电源抑制比（PSRR）和较低的温度系数。该电路采用SIMC 0.18-μm CMOS工艺实现。利用Cadence/Spectre仿真器进行仿真,结果表明,在1.8 V电源电压下,-40～125℃范围内,温度系数为9.699 ppm/℃;在27℃下,10 Hz时电源抑制比为90.2 dB,20 kHz时为74.97 dB。%An optimized PSR enhance stage was inserted in OPAMP of the classic CMOS bandgap voltage reference source, and one CMOS bandgap voltage reference source for audio Σ-ΔA/D converter was designed. It featured high power supply rejection ratio (PSRR) and low temperature coefficient with first-order temperature compensation. The circuit was implemented in SMIC 0.18-μm CMOS process. The simulation results in Cadence/Spectre showed that the circuit had a temperature coefficient of 9.699ppm/℃ at 1.8V supply voltage from -40℃ to 125℃ and a PSRR up to 90.2 dB (10 Hz) and 74.97 dB(20 kHz) at 27℃.