MK3722
VCXO
PLUS AUDIO CLOCK FOR
STB
Description
The MK3722 is a low cost, low jitter, high performance
VCXO and PLL clock synthesizer designed to replace
expensive discrete VCXOs and multipliers. The
patented on-chip Voltage Controlled Crystal Oscillator
accepts a 0 to 3.3 V input voltage to cause the output
clocks to vary by ±115 ppm. Using ICS’ analog/digital
Phase-Locked Loop (PLL) techniques, the device uses
an inexpensive 27 MHz pullable crystal input to
produce a reference output and a selectable audio
clock.
ICS manufactures the largest variety of VCXO based
timing devices for all applications. Consult ICS to
eliminate VCXOs, crystals, and oscillators from your
board.
The frequency of the on-chip VCXO is adjusted by an
external control voltage connected to VIN. Because
VIN is a high impedance input, it can be driven directly
from an PWM RC integrator circuit.
Features
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Packaged in 16 pin TSSOP
Replaces a VCXO and oscillator
Operating voltage of 3.3V
Provides output of 27 MHz plus audio clock
Uses an inexpensive 27 MHz pullable crystal
On-chip patented VCXO with pull range of 230 ppm
(minimum)
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VCXO tuning voltage of 0 to 3.3 V
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Advanced, low power, sub-micron CMOS process
Block Diagram
VDD
3
S2:S0
VIN
X1
27 MHz
Pullable
Crystal
3
PLL/Clock
Synthesis
Circuitry
ACLK
X2
Voltage
Controlled
Crystal
Oscillator
3
27MHz
GND
PDTS
MDS 3722 B
In tegr ated C ir cu it S yst ems
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1
5 25 Ra ce Str eet, San Jose, C A 95 126
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Revision 092502
tel ( 408) 2 95-9 800
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www. i c s t. c om