114results about How to "Suppress high frequency noise" patented technology

The invention relates to a self-biased phase-locked loop which comprises a phase frequency detector, a charge pump, a loop filter, a voltage controlled oscillator, a frequency demultiplier and a biased current converter, wherein charging or discharging current output by the charge pump is equal to a first control current; a resistor of the loop filter is controlled by a first control voltage and a second control voltage, the second control voltage is adjusted according to the first control voltage and a second control current, and the loop filter increases or reduces the first control voltage according to the charging or discharging current output by the charge pump; the voltage controlled oscillator generates oscillating voltage and biased current according to the first control voltage, and accelerates or slowers oscillating frequency according to the increase or the reduction of the oscillating voltage; and the biased current converter converts the biased current to a first control current and the second control current, wherein the first control current is equal to the ratio of the biased current and a constant; and the second control current is equal to the ratio of the biased current and the frequency demultiplication number of the frequency demultiplier. The self-biased phase-locked loop has the characteristics of simple current and low dithering.

A dust collection unit for a vacuum cleaner includes a first filtering chamber filtering relatively large foreign objects, a second filtering chamber filtering relatively small foreign objects when air exhausted from the first filtering chamber is introduced into the second filtering chamber, an exhaust member disposed above the filtering chambers to guide airflow, a storing chamber disposed under the filtering chambers to store the foreign objects filtered in the filtering chambers, a sealing member sealing bottoms of the filtering chambers, and a rectifying unit formed on an exhaust side of the second filtering chamber to rectify airflow, thereby reducing noise generated by the airflow.

An interleaving striped capacitor substrate structure for pressing-type print circuit boards is disclosed. To meet the high-frequency, high-speed, and high-density requirements in modern electronic systems, the interleaving striped capacitor substrate structure uses several dielectric materials of different dielectric coefficients to make a dielectric layer. One dielectric layer can be stacked on another to form a multi-layered capacitor substrate so that a single capacitor substrate can provide the highest capacitance required for the decoupling capacitor to suppress high-frequency noise signals, and the lower dielectric coefficient substrate required for high-speed signal transmission. This simultaneously achieves the effects of reducing high-frequency transmission time and suppressing high-frequency noise.

A LSI has a plurality of separate power source systems, and an ESD protection circuit connected between ground lines of two of the power source systems. The protection circuit includes a pair of thyristors connected parallel to one another in opposite directions between the ground lines.