摘要
设计了一种用于音频领域的高精度大动态范围对数型数字增益控制器,实现了在音频范围内的电压到电压对数型衰减控制,衰减范围为0^-94.5 dB,单位衰减量为-1.5 dB。增益控制字为8位信号DIN[7∶0],内部使用18位R-2R结构DAC实现精确衰减控制,使用对数译码逻辑减少输入控制字位数。设计了具有低噪声特性的轨到轨运算放大器,等效输入噪声仅为10.7 nV/Hz@1 kHz。仿真结果表明,设计的对数型数字增益控制器具有工作电压低、动态范围大、衰减精度高、等效输入噪声低等优点。
A high precision audio logarithmic digital gain controller（DGC） with wide dynamic range was proposed.The DGC realized logarithmic gain control from input to output with attenuation range from 0 dB to-94.5 dB in a resolution of-1.5 dB.With digital input of DIN,the circuit contained an 18-bit R-2R DAC,which controlled attenuation precisely.A logarithmic decode circuit was used to reduce the number of digital control bits.A low noise rail-to-rail op amp was designed,which had an equivalent input noise of 10.7 nV/Hz@ 1 kHz.Simulation results showed that the proposed DGC featured low supply voltage,wide dynamic range,precise attenuation and low equivalent input noise.
出处
《微电子学》
CAS
CSCD
北大核心
2011年第3期424-427,460,共5页
Microelectronics
基金
国家科技支撑计划项目(2008BAI50B08)
