1 / 8 page
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. *A
December 22, 2002
2
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
0000
8x
0001
12x
0010
16x
0011
20x
0100
16x
0101
24x
0110
32x
0111
40x
1000
4x
1001
6x
1010
8x
1011
10x
1100
8x
1101
12x
1110
16x
1111
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
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
