PRELIMINARY INFORMATION
ICS3726-12
HIGH PERFORMANCE VCXO
Description
Features
The ICS3726-12 is a low cost, low-jitter,
• Packaged in 8-pin SOIC
high-performance 3.3 volt VCXO designed to replace
expensive discrete VCXOs modules. The ICS3726-12
offers a wider operating frequency range and improved
power supply noise rejection. The on-chip Voltage
Controlled Crystal Oscillator accepts a 0 to 3.3 V input
voltage. Using ICS’ patented VCXO techniques, the
device uses an inexpensive external pullable crystal in
the range of 20 to 52 MHz to produce a VCXO output
clock at that same frequency.
• Operational frequency range of 20 MHz to 52 MHz
• Uses an inexpensive external crystal
• On-chip patented VCXO with pull range of 400 ppm
• VCXO tuning voltage of 0 to VDD
• Operating voltage of 3.3 V
• 12 mA output drive capability at TTL levels
• Works with surface mount crystal with CL=10 pF
• Advanced, low-power, sub-micron CMOS process
• Available in Pb (lead) free package
This part is ideal for Set-Top Box, multimedia clock
synthesizers and ADSL/VDSL applications.
The frequency of the on-chip VCXO is adjusted by an
external control voltage input into pin VIN. Because
VIN is a high-impedance input, it can be driven directly
from an PWM RC integrator circuit. Frequency output
increases with VIN voltage input. The usable range of
VIN is 0 to VDD.
Block Diagram
VDD
VIN
Voltage
Controlled
Crystal
X1
X2
20 to 52 MHz
20 to 52 MHz
Pullable Crystal
Clock (REFOUT)
Oscillator
Optional tuning
crystal capacitors
GND
MDS 3726-12 B
1
Revision 120505
Integrated Circuit Systems ● 525 Race Street, San Jose, CA 95126 ● tel (408) 297-1201 ● www.icst.com