Frequency Generator and Buffers for Mobile Pentium Systems
General Description
The ICS9159-12 generates all clocks required for mobile
microprocessor systems based on Pentium/Mobile Triton
chip sets. Three different reference frequency multiplying
factors are externally selectable with smooth frequency
transitions. These multiplying factors can be customized
for specific plications. A test mode is provided to drive all
clocks directly.
High drive BCLK outputs provide greater than 1V/ns slew
rate into 30pF loads. PCLK outputs provide better than 1V/
ns slew rate into 20pF loads while maintaining ±5% duty
cycle.
Block Diagram
Features
Generates 14 clocks including processor, disk
and reference
Meets all Pentium/Mobile Triton 82430MX
requirments
Independent buffers provide 4 and 6 clock copies
Buffered clocks skew matched to ±250ps
Buffer inputs are 5V tolerant
Test clock mode eases system design
Selectable multiplying and processor/bus ratios
Custom configurations available
3.0V- 5.5V supply range
28pin, .209" SSOP package
ICS reserves the right to make changes in the device data identified in this publication
without further notice. ICS advises its customers to obtain the latest version of all
device data to verify that any information being relied upon by the customer is current
and accurate.
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ICS9159-12
Pin Descriptions
PIN NUMBERPIN NAMETYPEDESCRIPTION
8, 25VDDPWRPower for logic , CPU and fixed frequ ency output buffers.
1X1IN
2X2OUTXTAL output which includes XTAL load capacitance.
3OENINOEN tristates all outputs when low. This input has an internal pull-up device.
4BPININInput to BPIN(0:5) buffers.
5BHININInput to BHIN(0:3) buffers.
11, 23GNDPWRGround for logic, CPU and fixed frequency output buffers.
6, 7, 9, 10BH(0:3)OUT
13, 12FS(0:1)IN
14, 20VDDPWRPower for B CLK output buffers.
15, 16, 18 19,
21, 22
24CPUOUT
2624MOUTThe 24M clock is fixed at 24 MHz.
28, 27REF(0:1)OUT
BP(0:5)OUT
XTAL or external reference frequency input. This input includes XTAL load
capacitance and feedback bias for a 10 - 30 MHz XTAL.
Buffered copies of the BHIN input, typically used to drive the PCI device clock
inputs at one half the CPU frequency.
Frequency multiplier select pins. See table below. These inputs have internal pull-up
devices.
Buffered copies of the BPIN input , typically used to drive the host device clock
inputs at the CPU fr equency. 17 VSS PWR Ground f or BCLK output buffers.
The CPU output, which is a multiple of the input reference frequency as shown in
the table above. Duty cy cle is 50/50±5% with a maximum freq uency of 100 MHz.
REF is a buffered copy of the crystal oscillator or reference input clock,
nominally 14.3 1818 MHz.
Note: BCLK buffers cannot be supplied with 5 volts (Pins 14 and 20) if CPU
and fixed frequencies (Pins 1, 8 and 26) are being supplied with 3 volts.
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ICS9159-12
Absolute Maximum Ratings
Supply Voltage .......................................................................................................... 7.0 V
Logic Inputs ....................................................................... GND 0.5 V to VDD +0.5 V
Ambient Operating Temperature ............................................................. 0°C to +70°C
Storage Temperature ........................................................................... 65°C to +150°C
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings
are stress specifications only and functional operation of the device at these or any other conditions above those listed
in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for
extended periods may affect product reliability.
Electrical Characteristics at 3.3V
VDD = 3.0 3.7 V
DC Char ac t e r i s t i c s
PARAMETERSYMBOLTEST C ONDI TI ONSMINTYPMAXUNI T S
Input Low VoltageV
Input High Volt ageV
Input Low CurrentI
Input High CurrentI
Output Low CurrentI
Output High CurrentI
Output Low CurrentI
Output High CurrentI
Output Low VoltageV
Outpu t Hi gh Volt a geV
Output Low VoltageV
Outpu t Hi gh Volt a geV
Supply Curr entI
OLVOL=0.8V; for PCLKS & BCLKS30.047.0-mA
OHVOL=2.0V; for PCLKS & BCLKS--66.0-42.0mA
OLVOL=0.8V; for fixed CLKs25.038.0-mA
OHVOL=2.0V; for fixed CLKs--47.0-30.0mA
OLIOL=15mA; for PCLKS & BCLKS-0.30.4V
OHIOH=-30mA; for PCLKS & BCLKS2.42.8-V
OLIOL=12.5mA; for fixed CLKs-0.30.4V
OHIOH=-20mA; for fixed CLKs2.42.8-V
CC@66.66 MHz; all ou t put s unl oade d-5 5110mA
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ICS9159-12
Electrical Characteristics at 3.3V
VDD = 3.0 3.7 V
PARAMETERSYMBOLTEST CONDITIONSMINTYPMAXUNITS
Rise Time 0.8 to 2.0VT
Fall Time 2.0 to 0.8VT
Rise Time 20% to 80%T
Fall Time 80% to 20%T
Duty Cycle [CPU]D
Duty Cycle, [REF(0:1)]D
Jitter, One SigmaT
Jitter, AbsoluteT
Jitter, One SigmaT
Jitter, AbsoluteT
Input Freque ncyF
Clock Skew WindowT
Clock Skew WindowT
Clock Skew WindowT
r20pF load-1.53ns
f20pF load-0.92n s
r20pF l oad-24.5ns
f20pF load-1.84 .25ns
t20pF load455055%
t20 pF load40-60%
j1sCPU Clock; Load=20pF, FOUT>25 MHz-50150ps
jabCPU Clock; Load=20pF, FOUT>25 MHz-250-250ps
j1sFixed CLK; Load=20pF; Comp. to the period-13%
jabFixed CLK; Load=20pF; Comp. to the period-25%
i-14.318-M Hz
skBH to BH; Load=20pF; @1.4V-50250ps
skBP to BP; Load=20pF; @1.4V-50250ps
skBH to BP; Load=2 0pF; @1.4V-100500ps
Pattern Number(2 or 3 digit number for parts with ROM code patterns)
Package Type
F=SSOP
Device Type (consists of 3 or 4 digit numbers)
Prefix
ICS=Standard Device
ICS reserves the right to make changes in the device data identified in this publication
without further notice. ICS advises its customers to obtain the latest version of all
5
device data to verify that any information being relied upon by the customer is current
and accurate.
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