Three-segment time-to-digital conversion circuit based on phase-locked loop

Abstract

The invention discloses a three-segment time-to-digital conversion circuit based on a phase-locked loop. Accurate counting clocks of a plurality of different frequencies and a plurality of uniform split phases are provided for a time-to-digital converter (TDC) through the phase-locked loop, so that accurate measurement of measured time by the TDC is ensured; the phase-locked loop is a three-order type-2 phase-locked loop, and comprises a phase frequency detector, a charge pump, a loop filter, a voltage-controlled oscillator, a frequency divider and an auxiliary state detection circuit; the TDC is a three-segment TDC including a high segment, a middle segment and a low segment; and the high segment of the TDC is provided with a 7-bit linear shift register. According to the three-segment time-to-digital conversion circuit, the phase-locked loop has the advantage of providing stable clocks of different frequencies and uniform phases, so that rough counting and fine quantitation and further fine quantitation of a measured time amount are finished; wide-range measurement is finished; and the measuring accuracy is ensured at the same time. Meanwhile, initial-phase time is measured at a same resolution, so that initial-phase time errors are eliminated, and the resolution and the measuring accuracy are kept constant at the same time.

Description

technical field [0001] The invention relates to a time interval measurement circuit, in particular to a three-stage time-to-digital conversion circuit that provides clocks of different stages based on a phase-locked loop. Background technique [0002] A time-to-digital converter is a conversion circuit that converts an analog time quantity into a digital signal, and is mainly used to measure time intervals. Different from traditional analog-to-digital converters, time-to-digital conversion circuits have the advantages of simple circuit structure, fast conversion speed and high conversion accuracy in measuring time analog quantities. In the measurement of many particles, the time of flight (Time of Flight, TOF) of the particle is an important physical quantity. According to TOF, the type of particle and the flight distance of the particle can be determined. It has a wide range of applications in deep space exploration and geological surveying and mapping. In terms of milita...

AI Technical Summary

Problems solved by technology

[0004] Purpose of the invention: In order to overcome the shortcoming that the traditional time-to-digital conversion circuit cannot balance the range and resolution, the present invention provides a three-stage time-to-digital conversion circuit based on a phase-locked loop, which improves the resolution while widening the range, without initial phase time error

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