CY2305 Cypress Semiconductor, CY2305 Datasheet - Page 8

• Manufacturer Part Number: CY2305
• Description: CY2305 and CY2309 as PCI and SDRAM Buffers
• Manufacturer: Cypress Semiconductor

The Self Adjusting Solution:
• This solution will automatically compensate for different
• CLKOUT must drive CK0 on the SDRAM module 1 and
SDRAM input loads (only on Module 1 and Module 2).
module 2 so that CLKOUT is always fully loaded (pin 42
on the SDRAM module).
CPUCLK
Decoding
Logic
REF
REF
S1
S2
CY2305
Zero Delay
Buffer
CY2309
Zero Delay
Buffer
CLKOUT
CLKOUT
CLKA1
CLKA2
CLKA3
CLKA4
CLKB1
CLKB2
CLKB3
CLKB4
CLK1
CLK2
CLK3
CLK4
8
CY2305 and CY2309 as PCI and SDRAM Buffers
• SDRAM modules must be installed in order (module 1 first
• Module 2 and 3 clocks are three-stated when those
• Module 1 clocks can only be three-stated by three-stating
and module 3 last).
SDRAM modules are not present, but CLKOUT will contin-
ue to run.
CPUCLK which will also three-state modules 2 and 3.
SDRAM Module 1
SDRAM Module 2
SDRAM Module 3
Module Sense
Module Sense