A SHA-less 14-bit, 100-MS/s pipelined ADC with comparator offset cancellation in background

【摘要】 A 14-bit 100-MS/s pipelined analog-to-digital converter(ADC) without dedicated front-end sampleand-hold amplifier(SHA) is presented. In addition to elaborate matching of the sampling network in the first stage,a background offset cancellation circuit is proposed in this paper to suppress the offset of the comparators in the first-stage sub-ADC, which ensures the overall offset does not exceed the correction range of the built-in redundant structure. Fabricated in a 0.18- m CMOS technology, the presented ADC occupies a chip area of 12 mm2, and consumes 237 m W from a 1.8-V power supply. Measurement results with a 30.1-MHz input sine wave under a sampling rate of 100 MS/s show that the ADC achieves a 71-d B signal-to-noise and distortion ratio(SNDR),an 85.4-d B spurious-free dynamic range(SFDR), a maximum differential nonlinearity(DNL) of 0.22 LSB and a maximum integral nonlinearity(INL) of 1.4 LSB.更多还原

【Abstract】 A 14-bit 100-MS/s pipelined analog-to-digital converter(ADC) without dedicated front-end sampleand-hold amplifier(SHA) is presented. In addition to elaborate matching of the sampling network in the first stage,a background offset cancellation circuit is proposed in this paper to suppress the offset of the comparators in the first-stage sub-ADC, which ensures the overall offset does not exceed the correction range of the built-in redundant structure. Fabricated in a 0.18- m CMOS technology, the presented ADC occupies a chip area of 12 mm2, and consumes 237 m W from a 1.8-V power supply. Measurement results with a 30.1-MHz input sine wave under a sampling rate of 100 MS/s show that the ADC achieves a 71-d B signal-to-noise and distortion ratio(SNDR),an 85.4-d B spurious-free dynamic range(SFDR), a maximum differential nonlinearity(DNL) of 0.22 LSB and a maximum integral nonlinearity(INL) of 1.4 LSB.更多还原