Six-bit 2.7-GS/s 5.4-mW Nyquist complementary metal-oxide semiconductor digital-to-analogue converter for ultra-wideband transceivers

Abstract

This study presents a 6-bit 2.7 GS/s low-power digital-to-analogue converter (DAC) for ultra-wideband transceivers. A ‘2(thermometer)+4(binary)’ segmented architecture is chosen to reach a compromise between the current source cell's area and the operating speed of the thermometer decoder. In addition, the proposed pseudo-thermometer structure improves the DAC's dynamic performance. The bipolar current source cell and latch clock delay technique are employed to reduce the power consumption in the analogue and digital parts, respectively. Moreover, the compact de-glitch latch presented in this study simplifies the conventional latch design and layout. This DAC was implemented in a standard 0.13 µm 1P8M complementary metal-oxide semiconductor technology with the active area of 0.0585 mm2. The measured differential non-linearity and integral non-linearity are less than 0.09 and 0.11 least significant bit, respectively. The measured spurious-free dynamic range is more than 36 dB over the Nyquist frequency at the sampling frequency of 2.7 GHz. The DAC consumes 5.4 mW with a near-Nyquist sinusoidal output at 2.7 GS/s, resulting in a better figure of merit of 31 fJ/conversion-step than other published arts.