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CY29948
Document #: 38-07288 Rev. *B
Page 2 of 7
Note:
1.
PD = Internal Pull-Down, PU = Internal Pull- UP
Output Enable/Disable
The CY29948 features a control input to enable or disable the
outputs. This data is latched on the falling edge of the input
clock. When SYNC_OE is asserted LOW, the outputs are dis-
abled in a LOW state. When SYNC_OE is set HIGH, the out-
puts are enabled as shown in Figure 1.
Pin Description[1]
Pin
Name
PWR
I/O
Description
3
PECL_CLK
I, PU
PECL Input Clock
4
PECL_CLK#
I, PD
PECL Input Clock
2TCLK
I, PU
External Reference/Test Clock Input
9, 11, 13, 15,
17, 19, 21, 23,
25, 27, 29, 31
Q(11:0)
VDDC
O
Clock Outputs
1
TCLK_SEL
I, PU
Clock Select Input. When LOW, PECL clock is selected and when
HIGH TCLK is selected.
5
SYNC_OE
I, PU
Output Enable Input. When asserted HIGH, the outputs are enabled
and when set LOW the outputs are disabled in a LOW state.
6
TS#
I, PU
Three-state Control Input. When asserted LOW, the output buffers
are three-stated. When set HIGH, the output buffers are enabled.
10, 14, 18, 22,
26, 30
VDDC
2.5V or 3.3V Power Supply for Output Clock Buffers
7VDD
2.5V or 3.3V Power Supply
8, 12, 16, 20,
24, 28, 32
VSS
Common Ground
TCLK
SYNC_OE
Q
Figure 1. SYNC_OE Timing Diagram