Data signal generating apparatus

Abstract

It is an object of the present invention to provide a data signal generating apparatus which is small in size, and can output the serial data in a desired sequence without assuming an indefinite state as well as being capable of dealing with the jitter measurement. In the data signal generating apparatus according to the present invention, synchronization meansfor synchronizing a data output unitwith a multiplexerhas a phase comparatorfor comparing the phase of a data synchronization clock signal outputted from a data output unitin synchronization with the timing to update parallel data, with the phase of a divided clock signal A produced by dividing the frequency of a reference clock signal CKby a plural number 'm' in the multiplexer, the signal A being used for determining the timing to performing parallel-serial conversion, a variable delay devicefor adding a desired delay to a data request signal A', the variable delay devicebeing constituted by an orthogonal modulation type delay device, and a control unitfor controlling a direct control signal to be inputted into the variable delay deviceon the basis of a comparing result obtained from the phase comparatorto synchronize the timing to have the data output unitupdate the parallel data with the timing to have the multiplexerperform parallel-serial conversion processing.