ASM3P2508SP

February 2005 www.DataSheet4U.com rev 0.4 ASM3P2508SP Clock Synthesizer and Frequency Generator with Peak EMI reduction Features ƒ ƒ ƒ ƒ ƒ ƒ ƒ ƒ Dual PLL based Architecture Operates with a 3.3V ±0.3V supply. Generates an EMI optimized Spread Spectrum PCI Clock output Generates a high accuracy non Spread T1 clock of ±25ppm accuracy. Generates a non spread system reference clock Low power CMOS design. Input frequency: 25 MHz. Outputs: Sys_ REF_CLK: 20 MHz T1 Clock: 25 MHz (±25 ppm) PCI_CLK: 33.33MHz Spread Spectrum ƒ Frequency deviation: -0.5% (Typ). Available in 8L SOIC Package. The ASM3P2508SP uses the most efficient and optimized modulation profile approved by the FCC. ASM3P2508SP modulates the output of a PLL in order to “spread” the bandwidth of a synthesized clock, and more importantly, decreases the peak amplitudes of its harmonics. This results in a significantly lower system EMI compared to the typical narrow band signal produced by oscillators and most frequency generators. Lowering EMI by increasing a signal’s bandwidth is called ‘spread spectrum clock generation’ (SSCG). In addition to the SSCG output, ASM3P2508SP generates two high accuracy clock signals T1 Clock @ 25.00MHz with +/- 25ppm stability, and a 20MHz Sys_ REF_CLK. ƒ Applications The ASM3P2508SP is targeted towards Consumer, Industrial, Data and Telecommunications applications. Product Description The ASM3P2508SP is a versatile Dual PLL based Clock Synthesizer and Frequency Generator optimised and ...