Exterded amount control device

Abstract

A spread range control apparatus of the present invention controls a clock generator, which generates a spread spectrum clock based on setting of spread data, so as to regulate a spread range of the spread spectrum clock. The spread range control apparatus includes: a loading quantity detection module that detects a loading quantity of a loading device, which is driven in response to a clock output from the clock generator; and a spread range setting module that sets spread data, which represents a spread range corresponding to the loading quantity detected by the loading quantity detection module, in the clock generator. This arrangement effectively protects a device having operations controlled in response to a clock from adverse effects possibly arising due to spread of the clock.

Description

technical field [0001] The present invention relates to a technique for controlling the spread amount of a clock generator for generating a frequency spread clock. Background technique [0002] Noise generated by various electronic devices can cause unwanted interference (EMI) to other electronic devices. Therefore, various restrictions are placed on noise generated by electronic equipment (hereinafter referred to as "EMI noise"). [0003] When developing and manufacturing electronic equipment, manufacturers usually try to reduce the EMI noise generated by the electronic equipment in order to make the manufactured electronic equipment meet the EMI noise limit. [0004] Among them, it is common that each device constituting an electronic device operates under the control of a clock supplied to each device. The frequency spectrum of a clock generally has amplitude peaks at the oscillation frequency of the clock (fundamental wave: f1) and frequencies corresponding to the harm...

AI Technical Summary

Problems solved by technology

At this time, if the frequency of the clock that controls the operation of the light source device is expanded and changed, there may be significant changes in the illumination brightness caused by the frequency change due to the magnitude of the expansion.

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