VT98521

VT98521 3.3V Clock Multiplier Applications = Low cost general-purpose clock source General Description The VT98521 is a 3.3V CMOS, clock multiplier integrated circuit. The device provides an excellent quality high frequency output clock from a lower frequency crystal or clock input. Tri-level selection inputs S0 and S1 are used to select any one of eight multipliers, stored in the on-board ROM, and apply it to the input to produce the desired output, up to 220 MHz. Phase Locked Loop (PLL) technology allows the device to use an input signal from an inexpensive crystal. When Output Enable (OE) is low, the clock output is in high impedance state. The VT98521, when used with an inexpensive crystal, provides a cost-effective clock source for most electronic systems. Features = = = = = = Low phase noise Zero ppm multiplication error Input clock frequency 5 - 50 MHz. Input crystal frequency 5 – 27 MHz Output clock frequencies up to 220 MHz. 5V-tolerant inputs and output = = = = Fully Compatible with all popular CPUs Duty Cycle - 45/55 up to 160 MHz. - 40/60 160 MHz to 220 MHz 25mA drive capability at TTL levels High-Z output for board level testing Figure 1. Functional Block Diagram Figure 2. Pin Assignment VDD GND 8-pin SOIC/MSOP S0 S1 Clock or Xtal X1/ICLK input PLL Clock Multiplier & ROM Xtal. Osc. Output Buffer CLK X1/ICLK VDD GND S1 1 2 3 4 8 7 6 5 X2 OE S0 CLK X2 Optional caps Output Enable 2002-02-25 Vaishali Semiconductor Page 1 www.vaishali.com...