ICS ICS9158-05M

ICS9158-05
Integrated
Circuit
Systems, Inc.
Advanced Information
Buffered Clock Generator for Pentium™ /Triton™ Systems
General Description
Features
The ICS9158-05 is a low cost frequency generator designed
specifically to clock Pentium systems using the Triton chip
set. Three copies of the CPU clock are available at 50, 60, or
66.7 MHz. Five copies of the synchronous BUS clock run at
half the CPU frequency. A 14.318 MHz REFCLK, 12 MHz,
KEYBD, and 24 MHz FLOPPY clock are also provided.
•
•
•
•
•
•
•
•
•
•
Each high drive output is capable of driving a 30pF load with
better than 1V/ns typical slew and have a duty cycle of 50±5%.
The synchronous outputs are skew controlled to within ±250ps
and CPU clocks lead BUS clocks by 2-5ns.
Glitch-free start and stop of the CPU and BUS clocks is
provided as well as a power-down mode with all clocks forced
low and the internal oscillators and PLLs powered-down.
Power-up time is less than 10ns. All frequency transitions are
gradual and meet the Intel cycle-to-cycle timing specification
for 486 and Pentium microprocessors.
3 CPU and 5 synchronous BUS clocks
50/60/66 MHz and glitch-free stop clock selections
±250ps skew between all synchronous outputs
Outputs drive up to 30pF load with 1V/ns slew
2-5ns early CPU clocks support Triton chip set
Compatible with 486 and Pentium CPUs
Consumes less than 10µA in power-down mode
On-chip loop filter components
3.0V - 5.5V supply range
24-pin SOIC package
Applications
•
Ideal for RISC or CISC systems such as 486, Pentium,
PowerPC,™ etc. requiring multiple CPU and
synchronous BUS clocks.
Block Diagram
Pentium and Triton are trademarks of Intel Corporation.
PowerPC is a trademark of Motorola Corporation
9158-05 Rev B 05/08/97
ADVANCE INFORMATION documents contain information on
new products in the sampling or preproduction phase of development. Characteristic data and other specifications are subject to
change without notice.
ICS9158-05
Advanced Information
Functionality
Pin Configuration
VDD = +5V±10%, TA=0°C to 70°C unless otherwise stated
OE
PD#
FS1
FS0
CPU
Ratio
1
1
1
1
0
0
0
1
14/4xX1
14/3xX1
1
1
1
1
1
1
0
1
1
0
X
X
0
X
X
X
42/10xX1
(STOP)
(PWR
DOWN)
-
CPU
(0:2)
(MHz)
50
66.7
BUS
(0:4)
(MHz)
25
33.3
14.318
14.318
60
Low
30
Low
Low
*Low
*Low
Tristate Tristate
Tristate
PD# forces all outputs low and powers-down the oscillator and PLL
circuitry, minimizing power consumption. In order to ensure glitch-free start
and stop of the CPU and BUS clocks, PD# should be asserted after the
CPU and BUS clocks have stopped, and be deasserted 10ms (maximum
PLL lock time) prior to starting the clocks.
24-Pin SOIC
OE
1
PD#
1
FLOPPY (MHz)
24
KEYBD (MHz)
12
1
0
0
X
Low
Tristate
Low
Tristate
Pin Descriptions for ICS9158-05
PIN NUMBER
1
X1,X2,
REF
(MHz)
14.318
14.318
PIN NAME
REFCLK
TYPE
OUT
2
X2
OUT
3
X1
IN
4
5
6
VDD
GND
KEYBD
PWR
PWR
OUT
Crystal connection, which includes output crystal load capacitance.
Crystal connection, which includes crystal load capacitance and feedback bias
for a nominal 14.31818 MHz parallel-resonance 12pF crystal.
Digital POWER SUPPLY.
Digital GROUND.
12 MHz keyboard clock output.
7
8
9
10
11
FLOPPY
BUS0
AGND
OE
BUS1
OUT
OUT
PWR
IN
OUT
24 MHz floppy disk clock output.
BUS clock output.
ANALOG GROUND.
OUTPUT ENABLE. Tristates all outputs when low.*
BUS clock output.
12
13
14
15
16
GND
CPU0
CPU1
PD#
AVDD
PWR
OUT
OUT
IN
PWR
Digital GROUND.
CPU clock output.
CPU clock output.
Power-down input shuts off both PLL stages when low.*
ANALOG power supply.
17
18
19
20
21
BUS2
BUS3
GND
VDD
CPU2
OUT
OUT
PWR
PWR
OUT
CPU clock output.
BUS clock output.
Digital GROUND.
Digital POWER SUPPLY.
CPU clock output.
OUT
IN
IN
BUS clock output.
Clock frequency select #1.*
Clock frequency select #0.*
22
BUS4
23
FS1
24
FS0
* Input pin has internal pull-up to VDD.
DESCRIPTION
14.318 clock output.
2
ICS9158-05
Advanced Information
Absolute Maximum Ratings
AVDD, VDD referenced to GND . . . . . . . . . . . . . . . . 7V
Operating temperature under bias. . . . . . . . . . . . . . . . 0°C to +70°C
Storage temperature . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +150°C
Voltage on I/O pins referenced to GND. . . . . . . . . . . GND -0.5V to VDD +0.5V
Power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 Watts
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating
only and functional operation of the device at these or any other conditions above those indicated 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 5V
VDD = +5V±10%, TA =0°C to 70°C unless otherwise stated
DC Characteristics
PARAMETER
Input Low Voltage
Input High Voltage
Input Low Current
Input High Current
Output Low Voltage
Output High Voltage1
1
SYMBOL
VIL
VIH
IIL
IIH
VOL
VOH
Output Low Current
Output High Current1
Supply Current
Output Frequency Change over
Supply and Temperature1
Short circuit current1
IOL
IOH
IDD
Pull-up resistor value1
Input Capacitance1
Load Capacitance1
TEST CONDITIONS
VIN=0V (Pull-up)
VIN=VDD
IOL=20.0mA
IOH=-30mA
MIN
2.0
-20
-5
2.4
VOL=0.8V
VOH=2.0V
No load, 66 MHz
With respect to typical
frequency
45
ISC
Each output clock
25
RPU
Ci
CL
Input pin
Except X1, X2
Pins X1, X2
FD
TYP
0.25
3.5
MAX
UNITS
0.8
V
V
µA
µA
V
V
5
0.4
65
-55
67
-35
100
mA
mA
mA
0.002
0.01
%
56
mA
680
kΩ
pf
pf
8
20
Note 1: Parameter is guaranteed by design and characterization. Not 100% tested in production.
3
ICS9158-05
Advanced Information
Electrical Characteristics ( continued)
VDD = +5V±10%, TA=0°C to 70°C unless otherwise stated
AC Characteristics
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
Output Rise time, 0.8 to 2.0V
(Note 1)
tr
30pf load
-
1
1.5
ns
Rise time, 20% to 80% VDD
(Note 1)
tr
30pf load
-
2.5
3
ns
Output Fall time, 2.0 to 0.8V1
tf
30pf load
-
0.5
1.5
ns
Fall time, 80% to 20% VDD1
tf
30pf load
-
1.5
2
ns
Duty cycle1
dt
30pf load
45/55
48/52
55/45
%
Jitter, one sigma1
tj1s
0.5
2.0
%
Jitter, absolute
tjab
As compared with clock
period
2
5
%
Jitter, absolute
tjab
25-66MHz clocks
250
ps
Input Frequency
-5
-250
fi
14.318
Clock skew between CPU and
2XCPU outputs
Tsk
100
250
ps
Frequency Transition Time1
tft
13
20
ms
From 4 to 50 MHz
Note 1: Parameter is guaranteed by design and characterization. Not 100% tested in production.
4
MHz
ICS9158-05
Advanced Information
Electrical Characteristics at 3.3V
VDD = +3.3V±10%, TA =0°C to 70°C unless otherwise stated
DC Characteristics
PARAMETER
Input Low Voltage
Input High Voltage
SYMBOL
VIL
VIH
TEST CONDITIONS
MIN
IIL
IIH
VOL
VOH
VIN =0V(Pull-up)
VIN =VDD
IOL=10mA
IOH =-5mA
Output Low Current 1
Output High Current 1
Supply Current
Output Frequency Change over
Supply and Temperature1
IOL
IOH
IDD
VOL=0.2VDD
VOH =0.7VDD
No load, 66 MHz
With respect to typical
frequency
20
Short Circuit Current 1
ISC
RPU
Ci
CL
Each output clock
Input pin
Except X1, X2
Pins X1, X2
25
Pull-up Resistor Value 1
Input Capacitance 1
Load Capacitance1
MAX
0.8
2.0
Input Low Current
Input High Current
Output Low Voltage
Output High Voltage1
FD
TYP
-10
-5
0.1V DD
0.85VDD
UNITS
V
V
µA
µA
V
V
30
-15
43
-10
65
mA
mA
mA
0.002
0.01
%
56
900
8
20
mA
kΩ
pF
pF
AC Characteristics
PARAMETER
Output Rise time, 0.8 to 2.0V1
1
Rise time, 20% to 80% VDD
Output Fall time, 2.0 to 0.8V1
Fall time, 80% to 20% VDD1
Duty cycle1
Jitter, one sigma1
1
Jitter, absolute
Jitter, absolute1
Input Frequency
Clock skew window between
CPU and 2XCPU outputs1
Frequency Transition time 1
SYMBOL
tr
TEST CONDITIONS
30pF load
tr
tf
tf
dt
tj1s
tjab
30pF
30pF
30pF
30pF
load
load
load
load
tjab
fi
25-66 MHz clocks
As compared with clock
period
TYP
MAX
UNITS
-
1
3.0
ns
40/50
2.5
0.5
1.5
44/46
4.0
2.5
4.0
50/40
ns
ns
ns
%
0.5
2
2.0
5
%
%
300
ps
MHz
100
250
ps
13
20
ms
14.318
Tsk
tft
MIN
From 4 to 50 MHz
Note 1: Parameter is guaranteed by design and characterization. Not 100% tested in production.
5
ICS9158-05
Advanced Information
ICS9158-05 CPU Clock DecodingTable
Frequency Transitions
(using 14.318 MHz input. All frequencies in MHz)
A key feature of the ICS9158-05 is its ability to provide
smooth, glitch-free frequency transitions on the CPU and
BUS clocks when the frequency select pins are changed. The
frequency transition rate does not violate the Intel 486 or
Pentium specification of less than 0.1% frequency change
per clock period.
VDD=5V±10% or 3.3V±10%, TEMP=0-70°C
X1,X2,
REF
(MHz)
14.318
14.318
OE
PD#
FS1
FS0
CPU
Ratio
1
1
1
1
0
0
0
1
14/4xX1
14/3xX1
1
1
1
1
1
1
0
1
1
0
X
X
0
X
X
X
42/10xX1 14.318
(STOP)
14.318
(PWR
Low
DOWN)
Tristate
CPU
(0:2)
(MHz)
50
66.7
BUS
(0:4)
(MHz)
25
33.3
60
Low
30
Low
*Low
*Low
Tristate
Tristate
Using an Input Clock as a Reference
The ICS9158-05 is designed to accept a 14.318 MHz crystal
as the input reference. With some external changes, it is
possi-ble to use a crystal oscillator or other clock sources.
Please see application note AAN04 for details on driving the
ICS9158-05 with a clock.
PD# forces all outputs low and powers-down the oscillator
and PLL circuitry, minimizing power consumption. In order
to ensure glitch-free start and stop of the CPU and BUS
clocks, PD# should be asserted after the CPU and BUS clocks
have stopped, and be deasserted 10ms (maximum PLL lock
time) prior to starting the clocks.
OE
1
PD#
1
FLOPPY (MHz)
24
KEYBD (MHz)
12
1
0
0
X
Low
Tristate
Low
Tristate
6
ICS9158-05
Advanced Information
24 Lead SOIC
LEAD COUNT
DIMENSION L
24L
0.604
Ordering Information
ICS9158-05M
Example:
ICS XXXX-PPP M
Package Type
M=SOIC
Pattern Number (2 or 3 digit number for parts with ROM code patterns)
Device Type (consists of 3 or 4 digit numbers)
Prefix
ICS, AV=Standard Device; GSP=Genlock Device
7
ADVANCE INFORMATION documents contain information on
new products in the sampling or preproduction phase of development. Characteristic data and other specifications are subject to
change without notice.