A phase interpolator and its control method

Abstract

The invention provides a phase interpolator and a control method thereof. A weight unit in the phase interpolator comprises a first switch tube, a second switch tube, a third switch tube, a fourth switch, a first current source, a second current source and a standby load; when the weight unit is in an on state, the third switch tube and the fourth switch tube are conducted, and the first current source and the second current source output current through the first switch tube, the third switch tube, the second switch tube and the fourth switch tube; and when the weight unit is in an off state, the third switch tube and the fourth switch tube are disconnected, the first current source provides current for the standby load through the first switch tube and the second switch tube. When the weight unit is in the off state, nodes A, B and C have a voltage approximating to the voltage generated when the weight unit is turned on, therefore, all that is needed is to regulate the voltage of the nodes to a normal work voltage from such voltage, thus, switching transient effect of the weight unit can be weakened, and work performance of the phase interpolator can be improved.

Description

technical field [0001] The present invention relates to the technical field of phase interpolators, and more specifically, to a phase interpolator and a control method thereof. Background technique [0002] A phase interpolator can proportionally mix two periodic input signals with the same period but different phases to produce an output signal with the same period but an intermediate phase. [0003] An existing phase interpolator includes a first clock selection circuit, a second clock selection circuit, an encoding circuit and a clock mixer, wherein the input period of the first clock selection circuit is the same but the phases are 0, 180 , 90 and 270 four clock signals, the input period of the second clock selection circuit is the same as four clock signals with phases of 45, 225, 135 and 315 respectively, and the encoding circuit controls the first clock selection circuit and the second clock The selection circuit selects the adjacent first clock signal and second clo...

AI Technical Summary

Problems solved by technology

[0007] In view of this, the present invention provides a phase interpolator and its control method to solve the problem that the switching of the weight unit of the existing phase interpolator has a large instantaneous effect

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