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CY25818/19

Document #: 38-07362 Rev. *B

Page 5 of 7

SSCG Profiles

CY25818/19 SSCG products use a non-linear “optimized”
frequency profile as shown in

 Figure 6

 and 

Figure 7

. The use

of Cypress proprietary “optimized” frequency profile maintains
flat energy distribution over the fundamental and higher order
harmonics. This results in additional EMI reduction in
electronic systems.

Application Schematic

Notes: 

3. X

IN

 = 16.0 MHz; S0 = 1; SSCLK = 16.0 MHz; BW = –2.14%.

4. Xin = 32.0MHz; S0 = 1; SSCLK = 32.0 MHz; BW = -2.15%

Figure 6. CY25818 Spread Spectrum Profile

(Frequency vs. Time)

[3]

Figure 7. CY25819 Spread Spectrum Profile 

(Frequency vs. Time)

[4]

Vdd

1

8

14.3 M Hz

or

27.0 M Hz 

 

   

Vss

S0

XIN

  XOUT

SSCLK

Vdd

CY25818
CY25819

3

4

0.1 uF

C3

C2

C3

27 pF

27 pF

   14.3 MHz (CY25818)
   27.0 MHz (CY25819)

 

REFCLK

5

   2

7

PD#

6

Figure 8. Typical Application Schematic

[+] Feedback 

Содержание CY25818

Страница 1: ...3 mW typ 32 MHz Low cycle to cycle jitter SSCLK 250 ps typ REFOUT 275 ps typ Available in 8 pin 150 mil SOIC package Applications Printers and MFPs LCD panels and notebook PCs Digital copiers PDAs Aut...

Страница 2: ...versions Refer to the CY25568 CY25811 CY25812 and CY25814 products for other functions such as clock multiplication of 1 2 or 4 to generate a wide range of Spread Spectrum output clocks from 4 to 128...

Страница 3: ...iven by the following formula fmod fIN DR where fmod is the Modulation Rate fIN is the Input Frequency and DR is the Divider Ratio as given in Table 3 Maximum Ratings 1 2 Supply Voltage Vdd 5 5V Input...

Страница 4: ...CLK and REFCLK 0 4V to 2 4V 2 0 3 0 4 0 ns tfall1 Clock Fall Time SSCLK and REFCLK 0 4V to 2 4V 2 0 3 0 4 0 ns CDCin Input Clock Duty Cycle XIN 20 50 80 CDCout Output Clock Duty Cycle SSCLK and REFCLK...

Страница 5: ...cs This results in additional EMI reduction in electronic systems Application Schematic Notes 3 XIN 16 0 MHz S0 1 SSCLK 16 0 MHz BW 2 14 4 Xin 32 0MHz S0 1 SSCLK 32 0 MHz BW 2 15 Figure 6 CY25818 Spre...

Страница 6: ...awing and Dimensions All product and company names mentioned in this document may be the trademarks of their respective holders Ordering Information Part Number Package Type Product Flow CY25818SC 8 p...

Страница 7: ...18 19 Spread Spectrum Clock Generator Document Number 38 07362 REV ECN NO Issue Date Orig of Change Description of Change 112462 03 21 02 OXC New Data Sheet A 122701 12 28 02 RBI Added power up requir...

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