
2.5V or 3.3V, 200-MHz, 12-Output Zero Delay Buffer
CY29773
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
, CA 95134
•
408-943-2600
Document #: 38-07573 Rev. **
Revised August 27, 2003
Features
• Output frequency range: 8.33 MHz to 200 MHz
• Input frequency range: 6.25 MHz to 125 MHz
• 2.5V or 3.3V operation
• Split 2.5V/3.3V outputs
• ±2% max Output duty cycle variation
• 12 Clock outputs: drive up to 24 clock lines
• One feedback output
• Three reference clock inputs: LVPECL or LVCMOS
• 300-ps max output-output skew
• Phase-locked loop (PLL) bypass mode
• Spread Aware™
• Output enable/disable
• Pin-compatible with MPC9773 and MPC973
• Industrial temperature range: –40°C to +85°C
• 52-pin 1.0-mm TQFP package
Description
The CY29773 is a low-voltage high-performance 200-MHz
PLL-based zero delay buffer designed for high speed clock
distribution applications.
The CY29773 features one LVPECL and two LVCMOS
reference clock inputs and provides 12 outputs partitioned in
three banks of four outputs each. Each bank divides the VCO
output per SEL(A:C) settings (see Table 2. Function Table
(Configuration Controls)). These dividers allow output-to-input
ratios of 8:1, 6:1, 5:1, 4:1, 3:1, 8:3, 5:2, 2:1, 5:3, 3:2, 4:3, 5:4,
1:1, and 5:6. Each LVCMOS-compatible output can drive 50
Ω
series-
or
parallel-terminated
transmission
lines.
For
series-terminated transmission lines, each output can drive
one or two traces, giving the device an effective fanout of 1:24.
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 8 MHz to 200 MHz. For normal
operation, the external feedback input FB_IN is connected to
the feedback output FB_OUT. The internal VCO is running at
multiples of the input reference clock set by the feedback
divider (see Table 1. Frequency Table).
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.
Block Diagram
Pin Configuration
AV SS
MR#/OE
SCLK
SDA TA
FB_SEL2
PLL_EN
REF_SEL
TCLK_SEL
TCLK0
TCLK1
PECL_CLK
PECL_CLK#
AV DD
VSS
QB0
V DDQB
QB1
VSS
QB2
V DDQB
QB3
FB_IN
VSS
FB_OUT
VDD
FB_SEL0
1
2
3
4
5
6
7
8
9
10
11
12
13
39
38
37
36
35
34
33
32
31
30
29
28
27
14 15 16 17 18 19 20 21 22 23 24 25 26
52 51 50 49 48 47 46 45 44 43 42 41 40
C Y 29773
REF_SEL
0
1
0
1
Phase
Detector
VCO
LPF
Sync
Frz
D Q
QA0
Sync
Frz
D Q
Sync
Frz
D Q
Sync
Frz
D Q
Sync
Frz
D Q
Sync
Frz
D Q
0
1
/2
Power-On
Reset
Output Disable
Circuitry
Data Generator
/4, /6, /8, /12
/4, /6, /8, /10
/2, /4, /6, /8
/4, /6, /8, /10
Sync Pulse
PECL_CLK
PECL_CLK#
TCLK0
TCLK1
TCLK_SEL
FB_IN
FB_SEL2
MR#/OE
SELA(0,1)
2
SELB(0,1)
2
SELC(0,1)
2
FB_SEL(0,1)
2
SCLK
SDATA
INV_CLK
QA1
QA2
QA3
QB0
QB1
QB2
QB3
QC0
QC1
QC2
QC3
FB_OUT
SYNC
12
VCO_SEL
PLL_EN