Re-circulating time-to-digital converter (TDC)
First Claim
1. A re-circulating time-to-digital converter (TDC), comprising:
- a triggered reference ring oscillator (TRRO) configured, when triggered by a reference signal edge, to generate a periodic ring oscillator signal with a ring oscillator period that is a selected ratio of a voltage-controlled oscillator (VCO) period; and
a delay module configured to store, in a plurality of latches, samples of a VCO signal clocked by the periodic ring oscillator signal, wherein each latch is configured to generate an output of the sample, and each latch output represents a time difference polarity between the VCO signal and the periodic ring oscillator signal.
1 Assignment
0 Petitions
Accused Products
Abstract
A re-circulating time-to-digital converter (TDC) can include a triggered reference ring oscillator (TRRO) and a delay module. The triggered reference ring oscillator can, when triggered by a reference signal edge, generate a periodic ring oscillator signal with a ring oscillator period that is a selected ratio of a voltage-controlled oscillator (VCO) period. The delay module can store, in a plurality of latches, samples of a VCO signal docked by the periodic ring oscillator signal. Each latch can generate an output of the sample, and each latch output can represent a time difference polarity between VCO signal and TRRO signal. In another example, the re-circulating TDC can include the triggered reference ring oscillator, a digital frequency lock module, and a TDC post-process module. The digital frequency lock module can generate a ring oscillator control signal, which sets the ring oscillator period for the triggered reference ring oscillator. The TDC post-process module can generate a TDC output, which can be a binary representation of a phase difference between a reference signal and a VCO signal.
-
Citations
30 Claims
-
1. A re-circulating time-to-digital converter (TDC), comprising:
-
a triggered reference ring oscillator (TRRO) configured, when triggered by a reference signal edge, to generate a periodic ring oscillator signal with a ring oscillator period that is a selected ratio of a voltage-controlled oscillator (VCO) period; and a delay module configured to store, in a plurality of latches, samples of a VCO signal clocked by the periodic ring oscillator signal, wherein each latch is configured to generate an output of the sample, and each latch output represents a time difference polarity between the VCO signal and the periodic ring oscillator signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A re-circulating time-to-digital converter (TDC), comprising:
-
a triggered reference ring oscillator (TRRO) configured, when triggered by a reference signal edge, to generate a periodic ring oscillator signal with a ring oscillator period that is a selected ratio of a voltage-controlled oscillator (VCO) period; a digital frequency lock module configured to generate a ring oscillator control signal, wherein the ring oscillator control signal sets the ring oscillator period for the triggered reference ring oscillator; and a TDC post-process module configured to generate a TDC output, wherein the TDC output is a binary representation of a phase difference between a reference signal and a VCO signal. - View Dependent Claims (19, 20, 21, 22, 23)
-
-
24. A method for time-to-digital conversion, comprising:
-
when triggered by a reference signal edge, clocking from a triggered reference ring oscillator a periodic ring oscillator signal with a ring oscillator period that is a selected ratio of a voltage-controlled oscillator (VCO) period; sampling a VCO signal clocked by the periodic ring oscillator signal; storing the samples in a plurality of latches, wherein each latch is configured to store the sample for a different time interval; and transmitting a digital state of the plurality of latches in parallel. - View Dependent Claims (25, 26, 27, 28, 29, 30)
-
Specification