CY25200_09 Datasheet, PDF (1/11 Pages) Cypress Semiconductor – Programmable Spread Spectrum Clock Generator for EMI Reduction

CY25200
Programmable Spread Spectrum
Clock Generator for EMI Reduction
Features
■ Wide operating output (SSCLK) frequency range
❐ 3–200 MHz
■ Programmable spread spectrum with nominal 31.5 kHz
modulation frequency
■ Center spread: ±0.25% to ±2.5%
■ Down spread: –0.5% to –5.0%
■ Input frequency range
❐ External crystal: 8–30 MHz fundamental crystals
❐ External reference: 8–166 MHz clock
■ Integrated phase-locked loop (PLL)
■ Programmable crystal load capacitor tuning array
■ Low cycle-to-cycle jitter
■ 3.3V operation with 2.5V output clock drive option
■ Spread spectrum On and Off function
■ Power down or Output Enable function
■ Output frequency select option
■ Field-programmable
■ Package: 16 pin TSSOP
Benefits
■ Suitable for most PC peripherals, networking, and consumer
applications.
■ Provides wide range of spread percentages for maximum EMI
reduction to meet regulatory agency Electro Magnetic
Compliance (EMC) requirements. Reduces development and
manufacturing costs and time to market.
■ Eliminates the need for expensive and difficult to use higher
order crystals.
■ Internal PLL generates up to 200 MHz outputs; also generates
custom frequencies from an external crystal or a driven source.
■ Enables fine tuning of output clock frequency by adjusting
C_Load of the crystal. Eliminates the need for external C_Load
capacitors.
■ Application compatibility in standard and low power systems.
■ Provides ability to enable or disable spread spectrum with an
external pin.
■ Enables low power state or output clocks to High-Z state.
■ Enables quick generation of sample prototype quantities.
Logic Block Diagram
XIN/CLKIN 1
XOUT ₁₆
C_XOUT
OSC.
C_XIN
Q
Φ
VCO
P
PLL
Divider
Bank 1
Divider
Bank 2
Output
Select
Matrix
2
VDD
3
5
13 11
6
AVDD AVSS VSS VDDL VSSL
4 10
CP0 CP1
7 SSCLK1
8 SSCLK2
9 _SSCLK3
12 _SSCLK4
14 SSCLK5/REFOUT/CP2
15 _{SSCLK6/REFOUT/CP3}
Cypress Semiconductor Corporation • 198 Champion Court
Document #: 38-07633 Rev. *E
• San Jose, CA 95134-1709 • 408-943-2600
Revised May 22, 2008
[+] Feedback