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CY23S08
Document #: 38-07265 Rev. *H
Page 3 of 10
Spread Aware
Many systems designed now use the Spread Spectrum Frequency Timing Generation (SSFTG) technology. Cypress is one of the
pioneers of SSFTG development, and designed this product so as not to filter off the Spread Spectrum feature of the Reference input,
assuming it exists. When a zero delay buffer does not pass through the SS feature, the result is a significant amount of tracking skew
which may cause problems in systems requiring synchronization.
For more details on Spread Spectrum timing technology, please see Cypress’s application note EMI Suppression Techniques with
Spread Spectrum Frequency Timing Generator (SSFTG) ICs.
Table 2. Select Input Decoding
S2
S1
CLOCK A1–A4
CLOCK B1–B4
Output Source
PLL Shutdown
0
0
Three-State
Three-State
PLL
Y
0
1
Driven
Three-State
PLL
N
1
0
Driven
Driven
Reference
Y
1
1
Driven
Driven
PLL
N
Table 3. Available CY23S08 Configurations
Device
Feedback From
Bank A Frequency
Bank B Frequency
CY23S08–1
Bank A or Bank B
Reference
Reference
CY23S08–1H
Bank A or Bank B
Reference
Reference
CY23S08–2
Bank A
Reference
Reference/2
CY23S08–2H
Bank A
Reference
Reference/2
CY23S08–2
Bank B
2 X Reference
Reference
CY23S08–2H
Bank B
2 X Reference
Reference
CY23S08–3
Bank A
2 X Reference
Reference or Reference[1]
CY23S08–3
Bank B
4 X Reference
2 X Reference
CY23S08–4
Bank A or Bank B
2 X Reference
2 X Reference
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