VT83201
3.3V Low Phase Noise VCXO
(Voltage-Controlled Crystal Oscillator)
and PLL Clock Synthesizer
Applications
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DSL clock source
Set-top boxes
Telecom switching
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MPEG Video clock source
HDTV
General Description
The Vaishali VT83201 is a single-chip, integrated VCXO and Phase Locked Loop (PLL) clock synthesizer.
The device uses the VCXO and an analog Phase-Locked Loop (PLL) to accept a 10 MHz to 20 MHz, 30pF
(pull range of 200 ppm) crystal input, in order to produce either one or two output clocks. A 0 to 3V control
signal is used to fine tune the output clock frequency in the ±100ppm range. Select inputs S0 and S1 are
used for frequency and output selection.
Features
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3.3V supply operation
Packaged in 16-pin SOIC package
Replaces separate VCXO and multiplier
Uses inexpensive pullable crystal
On-chip VCXO with 200 ppm pull range (±100 ppm)
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5V-tolerant control inputs
Zero ppm synthesis error in both
clocks
Figure 1. Functional Block Diagram
VDD1
VDD2
VIN
X2
Load Cap Control
Output
Buffer
osc
Load
Caps
Low
Phase
Noise
PLL
Output
Buffer
X1
S1:S0
OE
CLK2
CLK1
10-20 MHz
Pullable
Crystal
2001-04-12
Vaishali Semiconductor
Page
1
www.vaishali.com
747 Camden Avenue, Suite C Campbell CA 95008
MDST-0011-01
Ph. 408.377.6060
Fax 408.377.6063