W158
Spread Spectrum System Frequency Synthesizer
CPU Output Jitter: ......................................................150 ps
Features
CPUdiv2, IOAPIC Output Jitter: ..................................250 ps
• Maximized EMI suppression using Cypress’s spread
spectrum technology
• Intel® CK98 Specification compliant
• 0.5% downspread outputs deliver up to 10 dB lower EMI
• Four skew-controlled copies of CPU output
• Eightcopies ofPCI output(synchronous w/CPU output)
• Four copies of 66-MHz fixed frequency 3.3V clock
• Two copies of CPU/2 outputs for synchronous memory
reference
• Three copies of 16.67-MHz IOAPIC clock, synchronous
to CPU clock
• One copy of 48-MHz USB output
• Two copies of 14.31818-MHz reference clock
• Programmable to 133- or 100-MHz operation
48 MHz, 3V66, PCI Output Jitter:................................500 ps
CPU0:3, CPUdiv2_ 0:1 Output Skew: .........................175 ps
PCI_F, PCI1:7 Output Skew: .......................................500 ps
3V66_0:3, IOAPIC0:2 Output Skew: ...........................250 ps
CPU to 3V66 Output Offset:........... 0.0 to1.5 ns (CPU leads)
3V66 to PCI Output Offset:.......... 1.5 to 3.0 ns (3V66 leads)
CPU to IOAPIC Output Offset: ...... 1.5 to 4.0 ns (CPU leads)
CPU to PCI Output Offset: ............ 1.5 to 4.0 ns (CPU leads)
Logic inputs, except SEL133/100#, have 250-kΩ pull-up
resistors
[1]
Table 1. Pin Selectable Frequency
SEL133/100#
CPU0:3 (MHz)
133 MHz
PCI
• Powermanagementcontrolpinsforclockstop and shut
down
• Available in 56-pin SSOP
1
0
33.3 MHz
33.3 MHz
100 MHz
Note:
Key Specifications
1. See Table 2 for complete mode selection details.
Supply Voltages: ...................................... V
V
= 3.3V±5%
= 2.5V±5%
DDQ3
DDQ2
Block Diagram
Pin Configuration
2
X1
X2
XTAL
OSC
REF0:1
GND
REF0
REF1
VDDQ3
X1
X2
GND
PCI_F
PCI1
VDDQ3
PCI2
PCI3
GND
PCI4
PCI5
VDDQ3
PCI6
1
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
VDDQ2
IOAPIC2
IOAPIC1
IOAPIC0
GND
2
3
4
CPU_STOP#
5
STOP
Clock
Logic
4
6
VDDQ2
CPU0:3
CPUdiv2_1
CPUdiv2_0
GND
VDDQ2
CPU3
CPU2
GND
VDDQ2
CPU1
CPU0
GND
VDDQ3
GND
7
8
9
2
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
÷2
CPUdiv2_0:1
3V66_0:3
SPREAD#
SEL0
PLL 1
SEL1
STOP
Clock
Logic
4
SEL133/100#
÷2/÷1.5
PCI7
1
7
GND
PCI_F
PCI1:7
GND
PCI_STOP#
CPU_STOP#
PWRDWN#
SPREAD#
SEL1
3V66_0
3V66_1
VDDQ3
GND
STOP
Clock
Logic
÷2
PWRDWN#
PCI_STOP#
SEL0
25
26
27
28
3V66_2
VDDQ3
48MHz
GND
3V66_3
VDDQ3
3
Power
Down
Logic
SEL133/100#
÷2
IOAPIC0:2
Three-state
Logic
1
PLL2
48MHz
Intel is a registered trademark of Intel Corporation.
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
•
CA 95134
•
408-943-2600
October 12, 1999, rev. **