CY25200 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
Benefits
• 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/Off function
• Power-down or Output Enable function
• Output frequency select option
• Suitable for most PC peripherals, networking, and consum-
er 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, and can
generate 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 sys-
tems.
• Provides ability to enable or disable spread spectrum with
an external pin.
• Enables low-power state or output clocks to High-Z state.
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
Pin Configuration
2
VDD
3
5
13 11
6
AVDD AVSS VSS VDDL VSSL
4 10
CP0 CP1
XIN 1
VDD 2
AVDD 3
CP0 4
AVSS 5
VSSL 6
SSCLK1 7
SSCLK2 8
16 ^XOUT
15 SSCLK6/REFOUT/CP3
14 SSCLK5/REFOUT/CP2
13 VSS
12 _SSCLK4
11 VDDL
10 _CP1
9 _SSCLK3
7 SSCLK1
8 SSCLK2
9 _SSCLK3
12 _SSCLK4
14 SSCLK5/REFOUT/CP2
15 _{SSCLK6/REFOUT/CP3}
Cypress Semiconductor Corporation • 3901 North First Street • San Jose, CA 95134 • 408-943-2600
Document #: 38-07633 Rev. *A
Revised April 22, 2004