VT98521
3.3V Clock Multiplier
Applications
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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
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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
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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
747 Camden Avenue, Suite C Campbell
MDST-0017-02
CA 95008
Ph. 408.377.6060
Fax 408.377.6063
VAISH [ VAISHALI SEMICONDUCTOR ]
