CY2305C
CY2309C
PRELIMINARY
3.3V Zero Delay Clock Buffer
CY2309C. It accepts one reference input and drives out five low
skew clocks. The -1H versions of each device operate up to
100-133 MHz frequencies and have higher drive than the -1
devices. All parts have on-chip PLLs which lock to an input clock
on the REF pin. The PLL feedback is on-chip and is obtained
from the CLKOUT pad.
Features
■ 10 MHz to 100-133 MHz operating range, compatiblewith CPU
and PCI bus frequencies
■ Zero input and output propagation delay
■ Multiple low skew outputs
The CY2309C has two banks of four outputs each that are
controlled by the select inputs as shown in the “Select Input
Decoding for CY2309C” on page 3. If all output clocks are not
required, BankB is three-stated. The input clock is directly
applied to the outputs by the select inputs for chip and system
testing purposes.
■ One input drives five outputs (CY2305C)
■ One input drives nine outputs, grouped as 4 + 4 + 1 (CY2309C)
■ 50 ps typical cycle-cycle jitter (15 pF, 66 MHz)
■ Test Mode to bypass phase locked loop (PLL) (CY2309C) only,
see “Select Input Decoding for CY2309C” on page 3
The CY2305C and CY2309C PLLs enter a power down mode
when there are no rising edges on the REF input. In this state,
the outputs are three-stated and the PLL is turned off. This
results in less than 12.0 μA of current draw for commercial
temperature devices and 25.0 μA for industrial temperature
parts. The CY2309C PLL shuts down in one additional case as
shown in the “Select Input Decoding for CY2309C” on page 3.
■ Available in space saving 16-pin 150 Mil SOIC or 4.4 mm
TSSOP packages (CY2309C), and 8-pin, 150 Mil SOIC
package (CY2305C)
■ 3.3V operation
In the special case when S2:S1 is 1:0, the PLL is bypassed and
REF is output from DC to the maximum allowable frequency. The
part behaves like a non-zero delay buffer in this mode and the
outputs are not three-stated.
■ Industrial temperature available
Functional Description
The CY2305C and CY2309C are die replacement parts for
CY2305 and CY2309.
The CY2305C or CY2309C is available in two or three different
configurations as shown in the “Ordering Information” on
page 11. The CY2305C-1 or CY2309C-1 is the base part. The
CY2305-1H or CY2309-1H is the high drive version of the -1. Its
rise and fall times are much faster than the -1s.
The CY2309C is a low cost 3.3V zero delay buffer designed to
distribute high speed clocks and is available in a 16-pin SOIC or
TSSOP package. The CY2305C is an 8-pin version of the
Logic Block Diagram for CY2309C
CLKOUT
MUX
PLL
REF
CLKA1
CLKA2
CLKA3
CLKA4
CLKB1
CLKB2
CLKB3
CLKB4
S2
Select Input
Decoding
S1
Cypress Semiconductor Corporation
Document Number: 38-07672 Rev. *F
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised July 5, 2007
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