A single die 124dB stereo audio delta sigma ADC with 111dB THD
A high performance, low power consumption, single die stereo delta sigma ADC is designed for professional audio and high precision measurement applications. A single loop, fifth order, thirty three level delta sigma analog modulator with positive and negative feedforward path is implemented. An interpolated multilevel quantizer with unevenly weighted quantization levels replaces a conventional 5 bit flash type quantizer in this design. These new techniques suppress signal dependent energy inside the delta sigma loop, reduce internal channel coupling and power consumption. Integrated with an on chip bandgap reference circuit and decimation filter, the ADC achieves 124 dB dynamic range (A weighted) 111 dB THD over 20 kHz bandwidth. Inter channel isolation is 130 dB. Total power consumption is less than 330 mW.
ESSCIRC 2007 33rd European Solid State Circuits Conference