This article proposes a power-efficient highly linear capacitor-array-based digital-to-time converter (DTC) using a charge redistribution constant-slope approach. A fringe-capacitor-based digital-to-analog converter (C-DAC) array is used to regulate the starting supply voltage of the constant discharging slope fed to a fixed-threshold comparator. The DTC operation mechanism is analyzed and design tradeoffs are investigated. The proposed DTC consumes merely 31 μW from a 1-V supply when clocked at 40 MHz, while achieving a fine resolution of 148 fs over a 9-bit range. The measured differential nonlinearity (DNL) and integral nonlinearity (INL) are 0.96/1.07 LSB.@en

This paper proposes a power-efficient capacitor-array-based digital-to-time converter (DTC) using a constant-slope approach. Fringe-capacitor-based digital-to-analog converter (C-DAC) array is used to regulate starting supply voltage of the constant slope fed to a fixed threshold comparator. The proposed DTC consumes only 15 μW from a 1V supply, while achieving fine resolution of 103 fs when running at 40 MHz. The measured INL and DNL are 0.73/0.35 LSB within a 5-bit range. The DTC achieves the best figure-of-merit of 8.5 fJ among state-of-the-art when normalizing the product of power and INL to the product of input frequency and range.@en