ICS ICS9169C-27

Integrated
Circuit
Systems, Inc.
ICS9169C-27
Frequency Generator for Pentium™ Based Systems
General Description
Features
The ICS9169C-27 is a low-cost frequency generator
designed specifically for Pentium based chip set systems.
The integrated buffer minimizes skew and provides all the
clocks required. A 14.318 MHz XTAL oscillator provides
the reference clock to generate standard Pentium
frequencies. The CPU clock makes gradual frequency
transitions without violating the PLL timing of internal
microprocessor clock multipliers.
•
•
•
•
Twelve CPU clock outputs provide sufficient clocks for the
CPU, chip set, memory and up to two DIMM connectors (with
four clocks to each DIMM). Either synchronous(CPU/2) or
asynchronous (32 MHz) PCI bus operation can be selected
by latching data on the BSEL input
Block Diagram
•
•
•
•
•
•
Twelve selectable CPU clocks operate up to 83.3MHz
Maximum CPU jitter of ± 200ps
Six BUS clocks support sync or async bus operation
250ps skew window for CPU outputs, 500ps skew
window for BUS outputs
CPU clocks BUS clocks skew 1-4ns (CPU early)
Integrated buffer outputs drive up to 30pF loads
3.0V - 3.7V supply range, CPU(1:6) outputs 2.5V(2.3752.62V) VDD option
32-pin SOIC/SOJ package
Logic inputs latched at Power-On for frequency selection
saving pins as Input/Output
48 MHz clock for USB support and 24 MHz clock for FD.
Pin Configuration
32-Pin SOIC/SOJ
Functionality
3.3V±10%, 0-70°C
Crystal (X1, X2) = 14.31818 MHz
VDD Groups:
VDD = X1, X2, REF/BSEL
VDDC1 = CPU1-6
VDDC2 = CPU7-12 & PLL Core
VDDB = BUS1-6
VDDF = 48/24 MHz
Latched Inputs:
L1 = BSEL
L2 = FS0
L3 = FS1
L4 = FS2
9169C-27 Rev C 04/16/98
ADDRESS
SELECT
FS2 FS1 FS0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
CPU(1:12)
(MHz)
50
60
66.6
REF/2
55
75
83.3
Tristate
BUS (1:6)MHz
48MHz
BSEL=1
25
30
33.3
REF/4
27.5
37.5
41.7
Tristate
BSEL=0
32
32
32
REF/3
32
32
32
Tristate
24MHz
REF
48
24
REF
48
24
REF
48
24
REF
REF/2
REF/4
REF
48
24
REF
48
24
REF
48
24
REF
Tristate Tristate Tristate
Pentium is a trademark on Intel Corporation.
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.
ICS9169C-27
Pin Descriptions
PIN NUMBER
1
PIN NAME
VDD
TYPE
DESCRIPTION
PWR
Power for device logic.
2
X1
IN
XTAL or external reference frequency input. This input
includes XTAL load capacitance and feedback bias for a
12-16MHz crystal, nominally 14.31818MHz. External crystal
load of 30pF to GND recommended for VDD power on faster
than 2.0ms.
3
X2
OUT
XTAL output which includes XTAL load capacitance.
External crystal load of 10pF to GND recommended for VDD
power on faster than 2.0ms.
GND
PWR
Ground for device logic.
CPU(1)
OUT
Processor clock output which is a multiple of the input
reference frequency.
4,11,20,26
5
FS0
6,7,9,10,15,16,17,18,19
8
IN
Frequency multiplier select pins. See shared pin description.*
CPU
(2:5) (8:12)
OUT
Processor clock outputs which are a multiple of the input
reference frequency.
VDDC1
PWR
Power for CPU(1:6) output buffers only. Can be reduced VDD
for 2.5V (2.375-2.62V) next generation processor clocks.
CPU(6)
OUT
Processor clock output which is a multiple of the input
reference frequency internal pull up devices.
12
FS1
13
CPU(7)
FS2
14
21,22,24,25,27,28
IN
Frequency multiplier select pin. See shared pin description.*
Processor clock output which is a multiple of the input
reference frequency internal pull up devices.
OUT
IN
Frequency multiplier select pin. See shared pin description.*
VDDC2
PWR
Power for CPU PLL, logic and CPU(7:12)output buffers. Must
be nominal 3.3V (3.0 to 3.7V)
BUS (6:1)
OUT
BUS clock outputs which are a multiple of the input
reference clock.
23
VDDB
PWR
Power for BUS clock buffers BUS(1:6).
29
VDDF
PWR
Power for fixed clock buffer (48 MHz, 24 Mhz).
30
24MHz
OUT
Fixed 24MHz clock (assuming a 14.31818MHz REF
frequency).
31
48MHz
OUT
Fixed 48MHz clock (assuming a 14.31818MHz REF
frequency).
REF
OUT
Fixed 14.31818MHz clock (assuming a 14.31818MHz REF
frequency).
32
BSEL
Selection for synchronous or asynchronous bus clock
operation. See shared pin programming description late in this
data sheet for further explanation.*
IN
* Internal pull-up will vary from 350K to 500K based on temperature.
2
ICS9169C-27
Shared Pin Operation Input/Output Pins
Test Mode Operation
The ICS9169C-27 includes a production test verification
mode of operation. This requires that the FS0 and FS1 pins
be programmed to a logic high and the FS2 pin be
programmed to a logic low(see Shared Pin Operation section).
In this mode the device will output the following
frequencies.
Shared Pin Operation - Input/Output Pins 5, 12, 13 and 32
on the ICS9169C-27 serve as dual signal functions to the
device. During initial power-up, they act as input pins. The
logic level (voltage) that is present on these pins at this time
is read and stored into a 4-bit internal data latch. At the end
of Power-On reset, (seeAC characteristics for timing values),
the device changes the mode of operation for these pins to
an output function. In this mode the pins produce the
specified buffered clocks to external loads.
Pin
REF
48MHz
24MHz
CPU (1:12)
BSEL=1
BUS (1:6)
BSEL = 0
To program (load) the internal configuration register for
these pins, a resistor is connected to either the VDD (logic 1)
power supply or the GND (logic 0) voltage potential. A 10
Kilohm(10K) resistor is used to provide both the solid
CMOS programming voltage needed during the power-up
programming period and to provide an insignificant load on
the output clock during the subsequent operating period.
Frequency
REF
REF/2
REF/4
REF2
REF/4
REF/3
Note: REF is the frequency of either the crystal connected
between the devices X1and X2 or, in the case of a device
being driven by an external reference clock, the frequency
of the reference (or test) clock on the device’s X1 pin.
Figs. 1 and 2 show the recommended means of implementing
this function. In Fig. 1 either one of the resistors is loaded
onto the board (selective stuffing) to configure the device’s
internal logic. Figs. 2a and b provide a single resistor loading
option where either solder spot tabs or a physical jumper
header may be used.
These figures illustrate the optimal PCB physical layout
options. These configuration resistors are of such a large
ohmic value that they do not effect the low impedance clock
signals. The layouts have been optimized to provide as little
impedance transition to the clock signal as possible, as it
passes through the programming resistor pad(s).
(Resistors are surface mount devices
shown schematically between 5.m. pads)
*use only one programming resistor
Fig. 1
3
ICS9169C-27
Fig. 2b
Fig. 2a
Fig. 3
4
ICS9169C-27
Technical Pin Function Descriptions
VDD
This is the power supply to the internal logic of the device as
well as the following clock output buffers:
clocks is control-led by the supply that is applied to the
VDD pin of the device. See the Functionality table at the
beginning of this data sheet for a list of the specific
frequencies that this clock operates at and the selection
codes that are necessary to produce these frequencies.
A. REF clock output buffers
B. BUS clock output buffers
C. Fixed clock output buffers
FS0, FS1, FS2
These pins control the frequency of the clocks at the CPU,
CPUL, BUS & SDRAM pins. See the Funtionality table at
the beginning of this data sheet for a list of the specific
frequencies that this clock operates at and the selection
codes that are necessary to produce these frequencies. The
device reads these pins at power-up and stores the
programmed selection code in an internal data latch. (See
programming section of this data sheet for configuration
circuitry recommendations.
This pin may be operated at any voltage between 3.0 and 5.5
volts. Clocks from the listed buffers that it supplies will
have a voltage swing from ground to this level. For the
actual guaranteed high and low voltage levels of these
clocks, please consult the AC parameter table in this data
sheet.
GND
This is the power supply ground return pin for the internal
logic of the device as well as the following clock output
buffers:
BSEL
This pin controls whether the BUS clocks will be synchronous
(run at half the frequency) with the CPU and CPUL clocks or
whether they will be asynchronous (run at a pre-programmed
fixed frequency) clock rate. It is a shared pin and is pro
grammed the same way as the frequency select pins.
A. REF clock output buffers
B. BUS clock output buffers
C. CPU clock output buffers
D. Fixed clock output buffers
VDDC (1:2)
These are the power supply pins for the CPU (1:6) and CPU
(7:12) clock buffers. By separating the clock power pins,
each group can receive the appropriate power decoupling
and bypassing necessary to minimize EMI and crosstalk
between the individual signals. VDDC1 can be reduced to
2.5V VDD for advanced processor clocks, which will bring
CPU (1:6) outputs at 0 to 2.5V output swings.
X1
This pin serves one of two functions. When the device is
used with a crystal, X1 acts as the input pin for the reference
signal that comes from the discrete crystal. When the device
is driven by an external clock signal, X1 is the device’ input
pin for that reference clock. This pin also implements an
internal crystal loading capacitor that is connected to ground.
See the data tables for the value of the capacitor.
48 MHz
This is a fixed frequency clock that is typically used to drive
Super I/O peripheral device needs.
X2
This pin is used only when the device uses a Crystal as the
reference frequency source. In this mode of operation, X2 is
an output signal that drives (or excites) the discrete crystal.
This pin also implements an internal crystal loading capacitor
that is connected to ground. See the data tables for the value
of the capacitor.
24 MHz
This is a fixed frequency clock that is typically used to drive
Keyboard controller clock needs.
REF
This is a fixed frequency clock that runs at the same frequency
as the input reference clock (typically 14.31818 MHz) is
and typically used to drive Video and ISA BUS
requirements.
CPU
This pin is the clock output that drives processor and other
CPU related circuitry that require clocks which are in tight
skew tolerance with the CPU clock. The voltage swing of
these clocks is controlled by that which is applied to the
VDDC pins of the device. See note on VDDC (1:2). See the
Functionality table at the beginning of this data sheet for a
list of the specific frequencies that this clock operates at and
the selection codes that are necessary to produce these
frequencies.
VDDB
This power pin supplies the BUS clock buffers.
VDDF
This power pin supplies the 48/24 MHz clocks.
BUS
This pin is the clock output that is intended to drive the
systems plug-in card bus. The voltage swing of these
5
ICS9169C-27
Absolute Maximum Ratings
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . 7.0 V
Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . GND –0.5 V to V DD +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, TA = 0 – 70° C unless otherwise stated
DC Characteristics
PARAMETER
SYMBOL
Input Low Voltage
TEST CONDITIONS
MIN
TYP
MAX
UNITS
VIL
-
-
0.2VDD
V
Input High Voltage
VIH
0.7VDD
-
-
V
Input Low Current
IIL
VIN = 0V
-28.0
-10.5
-
µA
Input High Current
IIH
VIN = VDD
-5.0
-
5.0
µA
Output Low Current1
IOL
VOL = 0.8V;
for CPU, BUS, Fixed CLKs
16.0
25.0
-
mA
Output High Current 1
IOH
VOL = 2.0V;
for CPU, BUS, Fixed CLKs
-
-30.0
-14.0
mA
Output Low Current1
IOL
VOL = 0.8V; for REF CLK
19.0
30.0
-
mA
Output High Current 1
IOH
VOL = 2.0V; for REF CLK
-
-38
-16.0
mA
Output Low Voltage1
VOL
IOL = 8mA;
for CPU, BUS, Fixed CLKs
-
0.3
0.4
V
Output High Voltage1
VOH
IOH = -8mA;
for CPU, BUS, Fixed CLKs
2.4
2.8
-
V
Output Low Voltage1
VOL
IOL = 10mA; for REF CLK
-
0.3
0.4
V
Output High Voltage1
VOH
IOH = -15mA; for REF CLK
2.4
2.8
-
V
Supply Current
IDD
@66.6 MHz; all outputs unloaded
-
90
180
mA
Note 1: Parameter is guaranteed by design and characterization. Not 100% tested in production.
6
ICS9169C-27
Electrical Characteristics at 3.3V
VDD = 3.0 – 3.7 V, TA = 0 – 70° C unless otherwise stated
AC Characteristics
PARAMETER
SYMBOL
Rise Time1
Tr1
Fall Time1
Tf1
Rise Time1
Tr2
Fall Time1
Tf2
Duty Cycle1
Dt
TEST CONDITIONS
20pF load, 0.8 to 2.0V
CPU & BUS
20pF load, 2.0 to 0.8V
CPU & BUS
20pF load, 20% to 80%
CPU & BUS
20pF load, 80% to 20%
CPU & BUS
20pF load @ VOUT=1.4V
CPU & BUS Clocks;
Load=20pF, BSEL=1
CPU & BUS Clocks;
Load=20pF, BSEL=1
MIN
TYP
MAX
UNITS
-
0.9
1.5
ns
-
0.8
1.4
ns
-
1.5
2.5
ns
-
1.4
2.4
ns
45
50
60
%
-
50
150
ps
-250
-
250
ps
Jitter, One Sigma1
Tj1s1
Jitter, Absolute1
Tjab1
Jitter, One Sigma1
Tj1s2
REF & Fixed CLKs; Load=20pF
-
1
3
%
Jitter, Absolute1
Tjab2
REF & Fixed CLKs; Load=20pF
-5
2
5
%
Input Frequency 1
Fi
12.0
14.318
16.0
MHz
Logic Input Capacitance 1
Crystal Oscillator Capacitance
Power-on Time1
1
CIN
Logic input pins
-
5
-
pF
CINX
X1, X2 pins
-
18
-
pF
From VDD=1.6V to 1st crossing of
66.6 MHz VDD supply ramp < 40ms
-
2.5
4.5
ms
ton
Clock Skew1
Tsk1
CPU to CPU; Load=20pF; @1.4V
-
150
250
ps
Clock Skew1
Tsk2
BUS to BUS; Load=20pF; @1.4V
-
150
250
ps
1
2.6
4
ns
0.5
1
ns
Clock Skew1
Tsk3
Clock Skew1
Tsk4
CPU to BUS; Load=20pF; @1.4V
(CPU is early)
CPU (@3.3V) to CPU (@2.5V)
(2.5V CPU is late)
Note 1: Parameter is guaranteed by design and characterization. Not 100% tested in production.
7
ICS9169C-27
0.818
SOIC Package
Ordering Information
ICS9169CM-27
ICS9169CJ-27
SOJ Package
Example:
ICS XXXX M - PPP
Pattern Number (2 or 3 digit number for parts with ROM code patterns)
Package Type
M=SOIC
J=SOJ
Device Type (consists of 3 or 4 digit numbers)
Prefix
ICS, AV = Standard Device
8
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.