Product Description The ASM3P2180A is a versatile spread spectrum frequency modulator designed specifically for a wide range of clock frequencies. ASM3P2180A reduces electromagnetic interference (EMI) at the clock source, allowing system wide reduction of EMI of down stream clock and data dependent signals. ASM3P2180A allows significant system cost savings by reducing the number of circuit board layers, and shielding that are traditionally required to pass EMI regulations. ASM3P2180A modulates the output of a single PLL in order to “spread” the bandwidth of a synthesized clock, thereby decreasing the peak amplitudes of its harmonics. This results in significantly lower system EMI compared to the typical narrow band signal produced by oscillators and most clock generators. Lowering EMI by increasing a signal’s bandwidth is called spread spectrum clock generation. ASM3P2180A uses the most efficient and optimized modulation profile approved by the FCC and is implemented by using a proprietary all-digital method.