I2041A-8TT
| Model | I2041A-8TT |
| Description | Clock Generator, 40.4MHz, CMOS, PDSO8, 4.40 MM, TSSOP-8 |
| PDF file | Total 9 pages (File size: 177K) |
| Chip Manufacturer | PULSECORE |
January 2006
rev 0.1
Versatile EMI Reduction IC
Features
FCC approved method of EMI attenuation
Provides up to 20dB of EMI suppression
Generates a low EMI spread spectrum clock of the
input frequency
Optimized for 25MHz to 60MHz input frequency
range
Internal loop filter minimizes external components
and board space
4 selectable spread ranges
SSON control pin for spread spectrum enable and
disable options
Low Cycle-to-cycle jitter
3.3V or 5.0V operating voltage
Low power CMOS design
Available in 8 pin SOIC and TSSOP Packages
P2041A
which provides system wide reduction of EMI of all clock
dependent signals. The P2041A allows significant system
cost savings by reducing the number of circuit board layers
and shielding that are traditionally required to pass EMI
regulations.
The P2041A uses the most efficient and optimized
modulation
profile
approved
by
the
FCC
and
is
implemented in a proprietary all-digital method.
The P2041A modulates the output of a single PLL in order
to “spread” the bandwidth of a synthesized clock and, more
importantly,
decreases
the
peak
amplitudes
of
its
harmonics. This result in significantly lower system EMI
compared to the typical narrow band signal produced by
oscillators and most frequency generators. Lowering EMI
by increasing a signal’s bandwidth is called “spread
spectrum clock generation”.
Product Description
The P2041A is a selectable spread spectrum frequency
modulator designed specifically for PC peripheral and
embedded controller markets. The
P2041A reduces
electromagnetic interference (EMI) at the clock source
Applications
The P2041A is targeted towards the embedded controller
market and PC peripheral markets including scanners,
MFP’s, printers, PDA, IA , and GPS devices.
Block Diagram
SR0
SR1
SSON
VDD
Modulation
XIN
XOUT
Crystal
Oscillator
Frequency
Divider
Feedback
Divider
PLL
Phase
Detector
Loop
Filter
VCO
Output
Divider
ModOUT
VSS
Alliance Semiconductor
2575 Augustine Drive
•
Santa Clara, CA
•
Tel: 408.855.4900
•
Fax: 408.855.4999
•
www.alsc.com
Notice: The information in this document is subject to change without notice.
