Abstract
This paper introduces a single-ended non-offset-cancelled flash ADC architecture, the “Threshold Inverter Quantizer” (TIQ). The TIQ is based on a CMOS inverter cell, in which the voltage transfer characteristics (VTC) are changed by systematic transistor sizing. As a result, a significant improvement of speed and reduction of area and power consumption is achieved. A sample TIQ based flash ADC chip including 3-bit, 4-bit and 6-bit versions together has been designed and fabricated with the 2 μ standard CMOS n-well technology. The proposed ADC cells are suitable for System-on-Chip (SoC) applications in high speed wireless products.
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Tangel, A., Choi, K. “The CMOS Inverter” as a Comparator in ADC Designs. Analog Integrated Circuits and Signal Processing 39, 147–155 (2004). https://doi.org/10.1023/B:ALOG.0000024062.35941.23
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DOI: https://doi.org/10.1023/B:ALOG.0000024062.35941.23