A VCO-based phase-expanding conversion designed for time-domain data converters

作者：Kao Shao Ku^*; Tang Yi Fu; Cheng Hsiang Chi

来源：MICROELECTRONICS JOURNAL, 2014, 45(7): 835-841.

DOI：10.1016/j.mejo.2014.04.025

• Phase-expanding converter (PEC)
• Time-domain
• data converter
• Voltage-controlled oscillator (VCO)
• VCO-based
• Multiphase
• Encoder

This paper presents the design of a VCO-based phase-expanding converter (PEC) that converts a time residue to improve time resolution for the time-domain data converters. A voltage controlled oscillator, which has multiphase structure, is combined with the multi-layer delay chain to generate quadruple phases, and thus expands the overall resolution. Since the architecture of this converter is flexible for different designs, we propose a 6-bit, 250 MHz PEC using a 16-phase, 1 GHz VCO with quadruple phase expander in this paper. Simulations in a 0.18 mu m the CMOS process indicate that the PEC has DNL less than +/- 0.2 LSB LSB, and INL less than +/- 0.3 LSB. Furthermore, with the frequency variation from 0.9 GHz to 1.1 GHz, the PEC still has DNL +/- 0.21 LSB, and INL +/- 0.29 LSB. Experiment results show that the DNL is 0.52-0.13 LSB and the INL is 0.21-0.66 LSB.

• 出版日期2014-7
• 单位长春大学