SCG2540 Datasheet, PDF (1/12 Pages) Connor-Winfield Corporation – Synchronous Clock Generators

2111 Comprehensive Drive
Aurora, Illinois 60505
Phone: [phone]
Fax: [phone]
www.conwin.com
SCG2540
Synchronous Clock
Generators
US Headquarters:
630-851-4722
European Headquarters:
[phone]
General Description
The SCG2540 is a mixed-signal phase lock loop
generating CMOS outputs from an intrinsically low jitter
voltage controlled crystal oscillator.
The SCG2540 can lock to one of two possible input
reference frequencies at 10 kHz which is selectable
using one input select pin.
Further features include an alarm output to indicate
Loss of Reference, LOR, or Loss of Lock, LOL. If only
one of the references is lost, the unit will disable its
phase detector and will signal an alarm, but will not
switch reference automatically. If both references are
lost, the SCG2540 will enter a Free Run state which will
guarantee a 20 ppm accurate output. Additionally, the
Free Run mode may be entered manually by applying a
high signal to the Force Free Run pin. If the unit is in
Free Run mode, the Free Run status pin will be high.
All outputs, except the Oscillator Output, may be put
into the tri-state high impedance condition for external
testing purposes by applying a high signal to the Reset/
Tri-State pin.
The filtered 10 kHz is derived from the oscillator
output. The offset between the filtered output and the
reference input will change with each reference
rearrangement.
The package maximum dimensions are .780” x .830”
x .35” on a six layer FR4 board with surface mount pins.
Parts are assembled using high temperature solder to
withstand surface mount reflow process.
Features
• Phase Locked Output
Frequency Control
• Intrinsically Low Jitter, Crystal
Oscillator Derived Output
• Two Selectable References
@ 10 kHz
• Alarm Output
• Tri-State Alarm Outputs and
Reference Output
• Force Free Run Function
• Automatic Free Run Operation
upon loss of both references
• Input Duty Cycle Tolerant
• 3.3 Volt Power Supply
• Small Size: 0.78” x 0.83” x 0.35”
maximum
• Surface Mount, DIL Package