摘要
基于SMIC 0.18μm工艺,设计了一款低功耗、低噪声的D类前置放大器。通过对常用运放的结构进行比较,选择了一种开关电容共模反馈电路的两级运放,并加入斩波结构降低噪声。用Cadence/Spectre仿真器进行仿真,仿真结果表明,该全差分运放的直流开环增益为65 dB,单位增益带宽为259.7 MHz,相位裕度为70°,转换速率为98 V/μs,静态功耗为1 mW。适合于现代的便携产品应用中。
A low power and low noise preamplifier of class D power amplifier based on the SMIC 0. 18 μm process is presented. By comparing basic operational amplifier, a two -stage operational amplifier with a switched capacitor common mode feedback circuit is chosen, and chopper structure is used to reduce the noise. The simulation results in Cadence/Spectre show that the fully - differential operational amplifier open - loop DC gain is 65 dB, the unity - gain bandwidth is 259. 7 MHz, the phase margin is 70°, the slew rate is 98 V/p.s, and the static power consumption is 1 mW. It＇ s suitable for modern portable products.
出处
《电声技术》
2013年第6期35-37,41,共4页
Audio Engineering
关键词
低噪声
低功耗
斩波
全差分
low noise
lowpower
chopper
fully - differential
