P1818 - Alliance Semiconductor

P1818 (P1818 - P1822) Low Power Mobile VGA EMI Reduction IC

The P18xx is a versatile spread spectrum frequency modulator designed specifically for a wide range of input clock frequencies from 10 to 160 MHz (see Input Frequency and Modulation Rate Selections). The P18xx can generate an EMI reduced clock from crystal, ceramic resonator, or system clock. The P18xx-A to P18xx-H offer various combinations of spread option.

Features

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• FCC approved method of EMI attenuation Provides up to 15 dB EMI reduction Generates a low EMI spread spectrum clock and a non-spread reference clock of the input frequency Optimized for frequency range from 10 MHz to 160 MHz P1818: 10 to 20 MHz P1819: 20 to 40 MHz P1820: 40 to 80 MHz P1821: 10 to 40 MHz P1822: 80 to 160 MHz Internal loop filter minimizes external components and board space
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• Selectable spread options: Down Spread and Center Spread Low inherent cycle-to-cycle jitter Eight spread % selections: +/-0.625% to
  –3.5% 3.3V operating voltage CMOS/TTL compatibl.