一种应用于PWM D类音频功率放大器的CMOS Rail-to-Rail比较器

A Rail-to-Rail CMOS comparator for PWM class-D audio power amplifier application

提出了一种应用于CMOS D类音频功率放大器的Rail-to-Rail PWM比较器,其输入级为Rail-to-Rail结构,输出级为AB类输出。基于CSMC 0.5μm CMOS工艺的BSIM3V3 Spice模型,采用Hspice对PWM比较器的特性进行了仿真,典型模型下的直流开环增益为50dB,电源抑制比为52dB,ICMR为0.04V^4.98V,传输时延为24.5ns,版图有效面积为210×75μm2。由于PWM比较器的良好性能参数,所以其不仅适用于D类音频功率放大器,也能应用于各类低频数据转换电路。

A comparator for PWM class-d audio power amplifiers is presented. The comparator＇s configuration of import stage is rail-to-rail, and the output stage is class-AB, Simulation results based on the CSMC 0.5 CMOS BSIM3V3 Spice typical process show that the DC open-loop gain is 50dB, the PSRR is 52dB, the ICMR is 0.04V-4.98V and the propagation delay time is 24.5ns. The active area of the PWM comparator is about 210 × 75μm^2.With the good performance parameters the comparator is adapted to class-D audio power amplifier, and suitable for all kinds of low frequency data converter.