CY29351_09 Datasheet, PDF (1/10 Pages) Cypress Semiconductor – 2.5V or 3.3V, 200 MHz, 9-Output Zero Delay Buffer

CY29351
2.5V or 3.3V, 200 MHz,
9-Output Zero Delay Buffer
Features
■ Output Frequency Range: 25 MHz to 200 MHz
■ Input Frequency Range: 25 MHz to 200 MHz
■ 2.5V or 3.3V Operation
■ Split 2.5V and 3.3V Outputs
■ ±2.5% Max Output Duty Cycle Variation
■ Nine Clock Outputs: Drive up to 18 Clock Lines
■ Two Reference Clock Inputs: LVPECL or LVCMOS
■ 150-ps Max Output-Output Skew
■ Phase-locked Loop (PLL) Bypass Mode
■ Spread Aware
■ Output Enable or Disable
■ Pin-compatible with MPC9351
■ Industrial Temperature Range: –40°C to +85°C
■ 32-pin 1.0-mm TQFP Package
Functional Description
The CY29351 is a low voltage high performance 200 MHz
PLL-based zero delay buffer designed for high speed clock distri-
bution applications.
The CY29351 features LVPECL and LVCMOS reference clock
inputs and provides nine outputs partitioned in four banks of one,
one, two, and five outputs. Bank A divides the VCO output by two
or four while the other banks divide by four or eight per SEL(A:D)
settings (Table 3, “Function Table,” on page 3). These dividers
enable output to input ratios of 4:1, 2:1, 1:1, 1:2, and 1:4. Each
LVCMOS compatible output can drive 50Ω series or parallel
terminated transmission lines. For series terminated trans-
mission lines, each output can drive one or two traces giving the
device an effective fanout of 1:18.
The PLL is ensured stable given that the VCO is configured to
run between 200 MHz to 500 MHz. This allows a wide range of
output frequencies from 25 MHz to 200 MHz. For normal
operation, the external feedback input, FB_IN, is connected to
one of the outputs. The internal VCO is running at multiples of
the input reference clock set by the feedback divider (Table 2,
“Frequency Table,” on page 3).
When PLL_EN# is LOW, PLL is bypassed and the reference
clock directly feeds the output dividers. This mode is fully static
and the minimum input clock frequency specification does not
apply.
Logic Block Diagram
SELA
PLL_EN
REF_SEL
TCLK
PECL_CLK
Phase
Detector
VCO
200 -
500 MHz
÷2 / ÷4
QA
LPF
÷4 / ÷8
QB
FB_IN
SELB
SELC
OE#
SELD
÷4 / ÷8
÷4 / ÷8
QC0
QC1
QD0
QD1
QD2
QD3
QD4
Cypress Semiconductor Corporation • 198 Champion Court
Document Number: 38-07475 Rev. *C
• San Jose, CA 95134-1709 • 408-943-2600
Revised March 17, 2009
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