Calibration method of variable delay circuit and variable delay circuit for calibration operation by this calibration method

摘要

Nominal delay amount that changes in the predetermined minimum nominal delay step d _s by controlling the slave connection state of M differently weighted delay stages that are slavely connected through the multiplexer by a control signal value. In the calibration method of a variable delay circuit for generating a correction delay amount corresponding to (D _s ), the delay amount (D _i ) measured for each of the given control signal values (CC _i ) is the minimum nominal delay of the variable delay circuit. The first and second errors (R _K = D _i- d) between the value (k) of the integer part of the answer obtained by dividing by step (d _s ) and two adjacent nominal delays (D _sk , D _{sk + 1} ). _s k, R _{k + 1} = d _s- R _k ) is calculated, and it is determined whether the first error R _k is equal to or less than the error maintained in the kth row of the calibration table, and if it is less than or equal to the column of the kth row of the calibration table. the calculated error to the first (R _k) and there is indicated a control signal value (CC _i) grant it, again keeping the second error (R _{k + 1)} the correction table to the K + 1 th row To determine whether an error or less, and less is indicated to the second error (R _{k + 1)} and the control signal value (CC _i) gave it calculates the column of the first row k + 1 from i = 0 i = 2 By executing up to ^M -1, control signal values for minimizing an error with respect to the nominal 1 delay amount are generated in rows 0 to K of the calibration table, respectively.