A low-power rail-to-rail 6-bit flash ADC based on a novel complementary average-value approach

ABSTRACT

In this paper, a 6-bit 300-MSample/s(MS/s) flash analog-to-digital converter (ADC) with a novel complementary average-value (CAV) approach is proposed. Input signal is pre-processed and then steered to be compared with a fixed reference voltage level, which greatly simplifies the comparator design and thus power consumption is reduced. In addition, rail-to-rail input range can be achieved by the proposed CAV technique, and the offset as well as bubble errors can therefore be minimized as a result of similar operation condition arrangement of the comparators. Simulated with TSMC 1P5M 0.25 µm process parameters, the results show that INL < ±04 LSB and DNL < ±01 LSB, and SNDR of 32.7dB can be achieved. The converter consumes 35mW at 2.5 V power supply and the power efficiency of this converter is only 3.3pJ/conv-step which compares favorably with other published results.

REFERENCES

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.1 Types and Design Styles
          Subjects: VLSI (very large scale integration)

General Terms:
Design

Keywords:
CMOS analog circuit, comparator, flash analog-to-digital converter, low power, rail-to-rail