英語 での Spread-spectrum の使用例とその 日本語 への翻訳
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Each chip in the spread-spectrum signal is used to generate an impulse signal.
The programmable frequency dithering feature provides low-EMI, spread-spectrum operation.
Maxim produces a family of spread-spectrum oscillators suitable for a wide range of applications.
Though designers and manufacturers compete,they are also joining in their effort to implement spread-spectrum systems.
Except for spread-spectrum parallel outputs, the MAX9248 is the same receiving circuit as the MAX9250.
One can demonstrate that all other signals not receiving the spread-spectrum code will remain as they are, that is, unspread.
For EMI reduction, SSCG(Spread-Spectrum Clock Generator) for diffused oscillation frequency at the PWM operation is optionally available.
The MAX9759 offers two modulation schemes: a fixed-frequency modulation(FFM)mode and a spread-spectrum modulation(SSM) mode.
This spread-spectrum system function is important when EMI is a concern for the end application, such as a switched-mode power supply.
Figure 4. Synchronizing the MAX1703 step-up converter to a spread-spectrum oscillator removes the peaks and causes the noise floor to rise.
Spread-spectrum communication system. Bandwidth Effects of the Spreading Operation Figure 2 illustrates the evaluation of signal bandwidths in a communication link.
The dither rateshould not be too high, since spread-spectrum causes a phase-shift in the system loop which needs to be compensated.
Spread-spectrum techniques are also effective in helping to meet regulatory standards for EMI, as these standards generally specify maximum EMI energy at certain points in the spectrum.
Spreading operation spreads thesignal energy over a wider frequency bandwidth. Spread-spectrum modulation is applied on top of a conventional modulation such as BPSK or direct conversion.
The use of spread-spectrum technology for RF reduction in unintentional transmitters in consumer products such as PCs, involves sweeping the clock that drives the PC over a band of frequencies.
Rather than having the spectral energy concentrated at the switching frequency andits harmonics, spread-spectrum modulation effectively spreads out the spectral energy of the output signal.
This indicates that this spread-spectrum CLK provides a 13dB EMI reduction on the spectrum peak. Figure 3.A CLK spectrum of the MAX9492 with and without spreading.
While it is possible that some spectralnoise may redistribute into the audio band with spread-spectrum modulation, this noise is suppressed by the noise-shaping function of the feedback loop.
Frequency profile of spread-spectrum CLK. To make the CLK spectrum flatter, a special curve, named a"Hershey KissTM," is used as the modulation waveform Figure 2.
Specialty Audio Devices-Maxim By flattening the wideband spectral components using Maxim's spread-spectrum modulation technology, EMI emissions that may be radiated by the speaker and cables are reduced.
Definitions Different spread-spectrum techniques are available, but all have one idea in common: the key(also called the code or sequence) attached to the communication channel.
Our Class D speaker amps use patented spread-spectrum modulation techniques in conjunction with sophisticated edge-rate control technology to minimize EMI emissions.
Spread-spectrum capability is built into each SerDes design to improve the electromagnetic interference(EMI) performance of the link, without the need for an external spread-spectrum clock.
That rejection also applies to other spread-spectrum signals that do not have the right key. Thus different spread-spectrum communications can be active simultaneously in the same band, such as CDMA.
When using the spread-spectrum oscillator as a clock source for microprocessors, be sure the μP can cope with tolerances on the duty cycles, rise and fall times, and other parameters associated with frequency variation in the source.
These systems often require spread-spectrum techniques, such as the higher rate extension of the direct-sequence spread spectrum(DSSS) system for wireless LAN application in the 2.4GHz band, in accordance with IEEE® 802.11b.
Using Spread-Spectrum Technology to Reduce Radiated Emissions While the term spread spectrum is used in techniques for reducing radiated emissions in consumer electronics, the application is different than that used in devices such as cordless phones.
MAX13253 1A Spread-Spectrum Push-Pull Transformer Driver for Isolated Power Supplies- Maxim Description Create a design and simulate using EE-Sim® tools: The MAX13253 is a 1A push-pull transformer driver designed to provide a simple solution for low-EMI isolated power supplies.
DS1080L Spread-Spectrum Crystal Multiplier- Maxim Description Create a design and simulate using EE-Sim® tools: The DS1080L is a low-jitter, crystal-based clock generator with an integrated phase-locked loop(PLL) to generate spread-spectrum clock outputs from 16MHz to 134MHz.
MAX31180 Spread-Spectrum Crystal Multiplier- Maxim Description Create a design and simulate using EE-Sim® tools: The MAX31180 is a low-jitter, crystal-based clock generator with an integrated phase-locked loop(PLL) to generate spread-spectrum clock outputs from 16MHz to 134MHz.