900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf






ICS

ICS951901 Datasheet Preview

ICS951901 Datasheet

Programmable Frequency Generator & Integrated Buffers

No Preview Available !

www.DataSheet4U.com
Integrated
Circuit
Systems, Inc.
ICS951901
Programmable Frequency Generator & Integrated Buffers for Pentium III Processor
Recommended Application:
Single chip clock solution for IA platform.
Output Features:
• 3 - CPU @ 2.5V
• 13 - SDRAM @ 3.3V
• 6 - PCI @3.3V,
• 2 - AGP @ 3.3V
• 1 - 48MHz, @3.3V fixed.
• 1 - 24/48MHz, @3.3V selectable by I2C
(Default is 24MHz)
• 2 - REF @3.3V, 14.318MHz.
Features:
• Programmable ouput frequency.
• Programmable ouput rise/fall time.
• Programmable SDRAM and CPU skew.
• Spread spectrum for EMI control typically
by 7dB to 8dB,
with programmable spread percentage.
• Watchdog timer technology to reset system
if over-clocking causes malfunction.
• Uses external 14.318MHz crystal.
• FS pins for frequency select
Skew Specifications:
• CPU - CPU: < 175ps
• SDRAM - SDRAM < 250ps (except SDRAM12)
• PCI - PCI: < 500ps
• CPU (early) - PCI: 1-4ns (typ. 2ns)
Pin Configuration
VDDA
1*(AGPSEL)REF0
1*(FS3)REF1
GND
X1
X2
VDDPCI
*(FS1)PCICLK_F
*(FS2)PCICLK0
PCICLK1
PCICLK2
PCICLK3
PCICLK4
GND
VDDAGP
AGPCLK0
AGPCLK1
GND
GND
*(FS0)48MHz
*(MODE)24_48MHz
VDD48
SDATA
SCLK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
48 VDDL
47 CPUCLK0
46 CPUCLK1
45 CPUCLK2
44 GND
43 VDDSDR
42 SDRAM0
41 SDRAM1
40 SDRAM2
39 GND
38 SDRAM3
37 SDRAM4
36 SDRAM5
35 VDDSDR
34 SDRAM6
33 SDRAM7
32 GND
31 SDRAM8/PD#
30 SDRAM9/SDRAM_STOP#
29 GND
28 SDRAM10/PCI_STOP#
27 SDRAM11/CPU_STOP#
26 SDRAM12
25 VDDSDR
48-Pin 300mil SSOP
* These inputs have a 120K pull down to GND.
1 These are double strength.
Block Diagram
PLL2
X1 XTAL
X2 OSC
PLL1
Spread
Spectrum
SDATA
SCLK
FS(3:0)
PD#
PCI_STOP#
CPU_STOP#
SDRAM_STOP#
MODE
AGP_SEL
Control
Logic
Config.
Reg.
/2
CPU
DIVDER
Stop
SDRAM
DIVDER
Stop
PCI
DIVDER
Stop
AGP
DIVDER
48MHz
24_48MHz
REF(1:0)
2
CPUCLK (2:0)
3
SDRAM (12:0)
13
PCICLK (4:0)
5
PCICLK_F
AGP (1:0)
2
Functionality
FS3 FS2 FS1
Bit2 Bit7 Bit6 Bit5
00 0 0
00 0 0
00 0 1
00 0 1
00 1 0
00 1 0
00 1 1
00 1 1
01 0 0
01 0 0
01 0 1
01 0 1
01 1 0
01 1 0
01 1 1
01 1 1
FS0 CPU SDRAM
Bit4 MHz MHz
0 66.67 66.67
1 66.67 100.00
0 66.67 133.34
1 75.00 75.00
0 83.31 83.31
1 90.00 90.00
0 95.00 95.00
1 100.00 66.67
0 100.00 100.00
1 100.00 133.34
0 105.00 105.00
1 112.00 112.00
0 117.99 117.99
1 124.09 124.09
0 133.34 100.00
1 133.34 133.34
PCI
MHz
33.33
33.33
33.33
37.50
33.32
30.00
31.67
33.33
33.33
33.33
35.00
33.60
35.40
31.02
33.33
33.33
AGP1
SEL=1
66.67
66.67
66.67
75.00
66.64
60.00
63.33
66.67
66.67
66.67
70.00
67.20
70.80
62.05
66.67
66.67
AGP0
SEL=0
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
0670B—07/15/04




ICS

ICS951901 Datasheet Preview

ICS951901 Datasheet

Programmable Frequency Generator & Integrated Buffers

No Preview Available !

www.DataSheet4U.com
ICS951901
General Description
The ICS951901 is a single chip clock solution for desktop
designs using 630S chipsets. It provides all necessary
clock signals for such a system.
The ICS951901 belongs to ICS new generation of
programmable system clock generators. It employs serial
programming I2C interface as a vehicle for changing
output functions, changing output frequency, configuring
output strength, configuring output to output skew, changing
spread spectrum amount, changing group divider ratio and
dis/enabling individual clocks. This device also has ICS
propriety 'Watchdog Timer' technology which will reset the
frequency to a safe setting if the system becomes
unstable from over clocking.
Power Groups
Analog
VDDA = X1, X2, Core, PLL
VDD48 = 48MHz, 24MHz, fixed PLL
Digital
VDDPCI = PCICLK_F, PCICLK
VDDSDR = SDRAM
VDDAGP=AGP, REF
MODE Pin Power Management Control Input
MODE
Pin 21
Pin 27
Pin 28
Pin 30
Pin 31
0 SDRAM11 SDRAM10
SDRAM9
SDRAM8
1 CPU_STOP# PCI_STOP# SDRAM_STOP# PD#
Pin Configuration
PIN NUMBER
1, 7, 15, 22, 25,
35, 43
2
3
4, 14, 18, 19, 29,
32, 39, 44
5
6
8
9
13, 12, 11, 10
17, 16,
20
PIN NAME
VDD
AGPSEL
REF0
FS3
REF1
GND
X1
X2
FS1
PCICLK_F
FS2
PCICLK0
PCICLK (4:1)
AGP (1:0)
FS0
48MHz
21 MODE
24_48MHz
23 SDATA
24 SCLK
27 CPU_STOP#
SDRAM11
28 PCI_STOP#
SDRAM10
SDRAM9
30
SDRAM_STOP#
31 PD#
26 33, 34, 36,
37, 38, 40, 41,
42
45, 46, 47
48
0670B—07/15/04
SDRAM8
SDRAM (12,
7:0)
CPUCLK (2:0)
VDDL
TYPE
PWR
IN
OUT
IN
OUT
PWR
IN
OUT
IN
OUT
IN
OUT
OUT
OUT
IN
OUT
IN
OUT
I/O
IN
IN
OUT
IN
OUT
OUT
IN
IN
OUT
OUT
OUT
PWR
DESCRIPTION
3.3V Power supply for SDRAM output buffers, PCI output buffers,
reference output buffers and 48MHz output
AGP frequency select pin.
14.318 MHz reference clock.
Frequency select pin.
14.318 MHz reference clock.
Ground pin for 3V outputs.
Crystal input,nominally 14.318MHz.
Crystal output, nominally 14.318MHz.
Frequency select pin.
PCI clock output, not affected by PCI_STOP#
Frequency select pin.
PCI clock output.
PCI clock outputs.
AGP outputs defined as 2X PCI. These may not be stopped.
Frequency select pin.
48MHz output clock
Pin 27, 28, 30, & 31 function select pin
0=Desktop 1=Mobile mode
Clock output for super I/O/USB default is 24MHz
Data pin for I2C circuitry 5V tolerant
Clock pin of I2C circuitry 5V tolerant
Stops all PCICLKs besides the PCICLK_F clocks at logic 0 level,
when input is low and MODE pin is in Mobile mode
SDRAM clock output
Stops all CPUCLKs clocks at logic 0 level, when input is low and
MODE pin is in Mobile mode
SDRAM clock output
SDRAM clock output
Stops all SDRAM clocks at logic 0 level, when input is low and
MODE pin is in Mobile mode
Asynchronous active low input pin used to power down the device
into a low power state. The internal clocks are disabled and the
VCO and the crystal are stopped. The latency of the power down will
not be greater than 3ms
SDRAM clock output
SDRAM clock outputs
CPU clock outputs.
Power pin for the CPUCLKs. 2.5V
2


Part Number ICS951901
Description Programmable Frequency Generator & Integrated Buffers
Maker ICS
Total Page 19 Pages
PDF Download

ICS951901 Datasheet PDF

View PDF for Mobile








Similar Datasheet

1 ICS951901 Programmable Frequency Generator & Integrated Buffers
ICS





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

Site map

Webmaste! click here

Contact us

Buy Components

Privacy Policy