Owner's manual

Copyright  Cirrus Logic, Inc. 2010
(All Rights Reserved)
http://www.cirrus.com
Fractional-N Clock Synthesizer & Clock Multiplier
Features
 Delta-Sigma Fractional-N Frequency Synthesis
– Generates a Low Jitter 6 - 75 MHz Clock
from an 8 - 75 MHz Reference Clock
 Clock Multiplier / Jitter Reduction
– Generates a Low Jitter 6 - 75 MHz Clock
from a Jittery or Intermittent 50 Hz to
30 MHz Clock Source
 Highly Accurate PLL Multiplication Factor
– Maximum Error Less Than 1 PPM in High-
Resolution Mode
 I²C™ / SPI™ Control Port
 Configurable Auxiliary Output
 Flexible Sourcing of Reference Clock
– External Oscillator or Clock Source
– Supports Inexpensive Local Crystal
 Minimal Board Space Required
– No External Analog Loop-filter
Components
General Description
The CS2000-CP is an extremely versatile system
clocking device that utilizes a programmable phase
lock loop. The CS2000-CP is based on a hybrid ana-
log-digital PLL architecture comprised of a unique
combination of a Delta-Sigma Fractional-N Frequency
Synthesizer and a Digital PLL. This architecture allows
for both frequency synthesis/clock generation from a
stable reference clock as well as generation of a low-
jitter clock relative to an external noisy synchronization
clock. The design is also unique in that it can generate
low-jitter clocks relative to noisy external synchroniza-
tion clocks at frequencies as low as 50 Hz. The
CS2000-CP supports both I²C and SPI for full software
control.
The CS2000-CP is available in a 10-pin MSOP pack-
age in Commercial (-10°C to +70°C) and Automotive
(-40°C to +85°C) grades. Customer development kits
are also available for device evaluation. Please see
“Ordering Information” on page 36 for complete details.
I²C / SPI
Auxiliary
Output
6 to 75 MHz
PLL Output
3.3 V
I²C/SPI
Software Control
8 MHz to 75 MHz
Low-Jitter Timing
Reference
Fractional-N
Frequency Synthesizer
Digital PLL & Fractional
N Logic
Output to Input
Clock Ratio
N
Timing Reference
PLL Output
Lock Indicator
50 Hz to 30 MHz
Frequency
Reference
Output to Input
Clock Ratio
Frequency Reference
MAY '10
DS761F2
CS2000-CP