CY2305 Cypress Semiconductor, CY2305 Datasheet
CY2305
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CY2305 Summary of contents
Page 1
... LOW (the input does not have to go LOW, it only has to stop). 5 Volt to 3.3 Volt Level Shifting The CY2305 and CY2309 can act as a 5-volt to 3.3-volt level shifter. The reference input pad is 5-volt signal-compatible. Since many system components still operate at 5 volts, this feature provides the capability to generate multiple 3 ...
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... Lead or Lag Adjustments To adjust the lead or lag of the outputs on the CY2305 or CY2309, one must understand the relationships between REF and CLKOUT, and the relationship between CLKOUT and the other outputs. To understand the relationship, first we need to understand a few properties of the CY2305 and CY2309 Phase Locked Loops ...
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... CLKA4 CLKB1 CLKB4 Advanced CY2305 and CY2309 as PCI and SDRAM Buffers of the outputs is that they all start the rising edge at the same time, but different loads will cause them to have different rise times and different times crossing the measurement thresh- olds. Since CLKOUT is the only output that is monitored, it will ...
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... Product Information The CY2305 Zero Delay Buffer The CY2305 is a 3.3-volt, five output zero delay buffer in an 8-pin 150-mil SOIC package. This part is intended for buffer- ing one clock into five clocks for PCI buffering or four clocks for use with 1 SDRAM module. The CY2305 is the simplest and easiest to use part in the Cypress zero delay buffer family ...
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... SDRAM DIMM Zero Delay Buffer Solution The CY2305 is an excellent clocking solution for a system using 1 SDRAM DIMM. The CY2305 comes in a very small 150-mil 8-pin SOIC package and is priced very aggressively for the high volume PC market. There are two solutions for ...
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... CLKOUT must drive CK0 on the SDRAM module 1 so that CLKOUT is always fully loaded (pin 42 on the SDRAM module). CPUCLK Decoding Logic CY2305 and CY2309 as PCI and SDRAM Buffers The Adjustable Delay Solution: • C must be equal to SDRAM module loading for zero load delay. ...
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... SDRAM DIMM Zero Delay Buffer Solution The CY2305 and CY2309 are excellent clocking solutions for a system using 3 SDRAM DIMMs. The CY2305 comes in a small 150-mil 8-pin SOIC package and the CY2309 comes in a small 150-mil 16-pin SOIC. Both buffers are priced very aggressively for the high volume PC market ...
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... SDRAM module). CPUCLK Decoding Logic CY2305 and CY2309 as PCI and SDRAM Buffers • SDRAM modules must be installed in order (module 1 first and module 3 last). • Module 2 and 3 clocks are three-stated when those SDRAM modules are not present, but CLKOUT will contin run. • ...
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... CPUCLK Decoding Logic Decoding Logic CY2305 and CY2309 as PCI and SDRAM Buffers The Adjustable Delay Solution: • C and C load1 for zero delay. • To make the SDRAM inputs lead or lag the reference input see the Lead or Lag Adjustments section of “ ...
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... The inclusion of Cypress Semiconductor products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress Semiconductor against all charges. CY2305 and CY2309 as PCI and SDRAM Buffers • SDRAM modules must be installed in order (module 1 first and module 4 last). • ...