Abstract: A time-to-digital converter (TDC) circuit includes self-referenced delay cell circuits each including: a first inverter coupled with a second inverter, the first inverter receiving a positive time signal representative of an incoming up signal; a third inverter coupled with a fourth inverter, the third inverter receiving a negative time signal representative of an incoming down signal; a first bank of capacitors coupled to a first node between the first/second inverters; and a second bank of capacitors coupled to a second node between the third/fourth inverters. Control logic generates first control signals, each with an up value, to selectively control the first bank of capacitors. Control logic generates second control signals, each with a down value, to selectively control the second bank of capacitors. The up values vary relative to the down values across the first control signals and the second control signals.

Abstract: A time-to-digital converter (TDC) circuit includes control logic and a first self-referenced delay cell circuit coupled to the control logic. The first self-referenced delay cell circuit includes: a first bank of capacitors coupled to a first node between a first positive input and a first positive output, where the first bank of capacitors is selectively controlled by a first control signal from the control logic, the first control signal including a first up value corresponding to a first positive threshold; and a second bank of capacitors coupled to a second node between a first negative input and a first negative output, where the second bank of capacitors is selectively controlled by a second control signal from the control logic, the second control signal including a first down value corresponding to a first negative threshold.

Abstract: A time-to-digital converter (TDC) circuit includes control logic and a first self-referenced delay cell circuit coupled to the control logic. The first self-referenced delay cell circuit includes: a first bank of capacitors coupled to a first node between a first positive input and a first positive output, where the first bank of capacitors is selectively controlled by a first control signal from the control logic, the first control signal including a first up value corresponding to a first positive threshold; and a second bank of capacitors coupled to a second node between a first negative input and a first negative output, where the second bank of capacitors is selectively controlled by a second control signal from the control logic, the second control signal including a first down value corresponding to a first negative threshold.