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3.3V, 125-MHz Multi-Output Zero Delay Buffer
CY29972
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
, CA 95134
•
408-943-2600
Document #: 38-07290 Rev. *C
Revised October 28, 2005
Features
• Output frequency up to 125 MHz
• 12 Clock outputs: frequency configurable
• 350 ps max. output-to-output skew
• Configurable output disable
• Two reference clock inputs for dynamic toggling
• Oscillator or crystal reference input
• Spread-spectrum-compatible
• Glitch-free output clocks transitioning
• 3.3V power supply
• Pin-compatible with MPC972
• Industrial temperature range: –40°C to +85°C
• 52-pin TQFP package
Table 1. Frequency Table[1]
VC0_SEL
FB_SEL2
FB_SEL1
FB_SEL0
FVC0
0
000
8x
0
001
12x
0
010
16x
0
011
20x
0
100
16x
0
101
24x
0
110
32x
0
111
40x
1
000
4x
1
001
6x
1
010
8x
1
011
10x
1
100
8x
1
101
12x
1
110
16x
1
111
20x
Note:
1. x = the reference input frequency, 200 MHz < FVCO < 480 MHz.
Block Diagram
Pin Configuration
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
XIN
XOUT
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
VSS
MR#/OE
SCLK
SDATA
FB_SEL2
PLL_EN
REF_SEL
TCLK_SEL
TCLK0
TCLK1
XIN
XOUT
VDD
VSS
QB0
VDDC
QB1
VSS
QB2
VDDC
QB3
FB_IN
VSS
FB_OUT
VDDC
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
CY29972
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