ICS9248-195
Integrated
Circuit
Systems, Inc.
Frequency Generator & Integrated Buffers for PENTIUM II/IIITM
& K6
RecommendedApplication:
KeySpecifications:
•
•
•
•
•
•
•
•
CPU Output Jitter @ 2.5V: <300ps
CPU Output Jitter @ 3.3V: <250ps
PCI Output Jitter @ 3.3V: <250ps
CPU Output Skew @ 2.5V: <175ps
CPU Output Skew @ 3.3V: <175ps
PCI Output Skew @ 3.3V: <500ps
440BX, MX, VIA PM/PL/PLE 133 style chip set, with
Coppermine orTualatin processor, for note book
applications.
OutputFeatures:
•
4 - CPUs @ 2.5V/3.3V
including 1 free running CPUCLK_F
PCI Early to PCI Skew @ 3.3V: typ = 3ns
SDRAM Output Skew @ 3.3V: <500ps
•
•
9 - SDRAM @ 3.3V
7 - PCI @ 3.3V, including 1 free running PCICLK_F
•
•
•
•
1 - PCI Early @ 3.3V
1 - 48MHz, @ 3.3V fixed.
1 - 24/48MHz @ 3.3V
2 - REF @3.3V, 14.318MHz.
Pin Configuration
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
VDDREF
*SPREAD/REF0
GNDREF
X1
1
2
REF1/FS2*
VDDLCPU
CPUCLK_F
CPUCLK0
GNDLCPU
CPUCLK1
CPUCLK2
CLK_STOP#
GNDSDR
SDRAM_F
SDRAM0
SDRAM1
VDDSDR
SDRAM2
SDRAM3
GNDSDR
SDRAM4
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
X2
VDDPCI
Features:
*CPU2.5_3.3#/PCICLK_F
*FS3/PCICLK0
GNDPCI
*SEL24_48#/PCICLK1
*SELPCIE_6#/PCICLK2
PCICLK3
•
•
•
Up to 137MHz frequency support
97MHz to support high-end AMD processor.
Support power management:CLK, PCI, stop and
Power down Mode from I2C programming.
PCICLK4
VDDPCI
BUFFER IN
GNDPCI
•
•
•
Spread spectrum for EMI control
Uses external 14.318MHz crystal
FS pins for frequency select
PCICLK5
PCICLK6/PCICLK_E
VDDCOR
PCI_STOP#
*Vtt_PWRGD/PD#
GND48
SDRAM5
VDDSDR
SDRAM6
SDRAM7
VDD48
SDATA
SCLK
48MHz/FS0*
24_48MHz/FS1*
48-Pin SSOP and TSSOP
* Internal Pull-up Resistor of 120K to VDD
Block Diagram
Functionality
Bit2
0
Bit6
0
Bit5
0
Bit4
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
CPUCLK
66.67
100.00
66.67
133.33
66.67
100.00
100.00
133.33
66.67
100.00
90.00
133.33
70.00
105.00
133.33
140.00
PCICLK
33.33
33.33
33.33
33.33
33.33
33.33
33.33
33.33
33.33
33.33
30.00
33.33
35.00
35.00
33.33
35.00
0
0
0
0
0
1
0
0
1
0
1
0
0
1
0
0
1
1
0
1
1
1
0
0
1
0
0
1
0
1
1
0
1
1
1
0
1
1
0
1
1
1
1
1
1
0375D—02/02/04