Abstract:
A CMOS analog and audio front-end circuit includes an enhanced analog-to-digital converter (ADC) that achieves a desired signal-to-noise-and-distortion (SNDR) and an analog-front-end transmit (TX) digital-to-analog converter (DAC). The enhanced ADC includes an improved single Op-Amp resonator coupled to a feed-forward loop and can substantially reduce signal transfer function (STF) peaking of the enhanced ADC. The CMOS analog and audio front-end circuit is integrated with a baseband processor.
Abstract:
A CT-SDADC of the present disclosure converts the analog input signal from a representation in an analog signal domain to a representation in a digital signal domain to provide the digital output signal. The CT-SDADC achieves the analog-to-digital conversion and ELDC by switching between two phases in the SAR sub-ADC: a sampling phase and a conversion phase. During the sampling phase, the SAR sub-ADC captures the analog input signal across multiple arrays of switchable capacitors. The conversion phase comprises a number of steps, and one or more bits of the digital output signal are resolved at each step of the conversion phase. A portion of the SC-DAC is driven by the delayed CT-SDADC output during the conversion phase to effectively compensate for excess loop delay caused by the CT-SDADC feedback loop.
Abstract:
A CT-SDADC of the present disclosure converts the analog input signal from a representation in an analog signal domain to a representation in a digital signal domain to provide the digital output signal. The CT-SDADC achieves the analog-to-digital conversion and ELDC by switching between two phases in the SAR sub-ADC: a sampling phase and a conversion phase. During the sampling phase, the SAR sub-ADC captures the analog input signal across multiple arrays of switchable capacitors. The conversion phase comprises a number of steps, and one or more bits of the digital output signal are resolved at each step of the conversion phase. A portion of the SC-DAC is driven by the delayed CT-SDADC output during the conversion phase to effectively compensate for excess loop delay caused by the CT-SDADC feedback loop.