ICS ICS9248YG-56-T

Integrated
Circuit
Systems, Inc.
ICS9248-56
Frequency Timing Generator for Pentium II Systems
General Description
Features
The ICS9248-56 is the Main clock solution for Notebook
designs using the Intel 440BX style chipset. Along with an
SDRAM buffer such as the ICS9179-03, it provides all
necessary clock signals for such a system.
•
Spread spectrum may be enabled by driving pin 26, SPREAD#
active (Low) at power-on. Spread spectrum typically reduces
system EMI by 8dB to 10dB. This simplifies EMI qualification
without resorting to board design iterations or costly shielding.
The ICS9248-56 employs a proprietary closed loop design,
which tightly controls the percentage of spreading over
process and temperature variations.
•
•
•
Block Diagram
•
•
Generates the following system clocks:
- 2CPU(2.5V) up to 100MHz.
- 6 PCI(3.3V) @ 33.3MHz (Includes one free running).
- 1 REF clks (3.3V) at 14.318MHz.
- 1 Fixed clock at 48MHz
- 1 Fixed clock at 48 or 24MHz
Skew characteristics:
- CPU – CPU<175ps
- PCI – PCI < 500ps
- CPU(early) – PCI = 1.5ns – 4ns.
Supports Spread Spectrum modulation for CPU and PCI
clocks, 0.5% down spread
Efficient Power management scheme through stop clocks
and power down modes.
Uses external 14.318MHz crystal, no external load cap
required for CL=18pF crystal.
28 pin 209mil SSOP and 173mil TSSOP
Pin Configuration
28 pin SSOP and TSSOP
Power Groups
VDD, GND = PLL core
VDDREF, GNDREF = REF(0:1), X1, X2
VDDPCI, GNDPCI = PCICLK_F, PCICLK (0:4)
VDD48, GND48 = 48MHz, 48/24MHz
Pentium is a trademark on Intel Corporation.
9248-56 Rev E 12/27/00
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.
ICS9248-56
Pin Descriptions
Pin number
Pin name
Type
Description
1
2
3
4
5,6,9,10,11
7
8
12
13
GNDREF
X1
X2
PCICLK_F
PCICLK (1:5)
GNDPCI
VDDPCI
VDD48
48 MHz
Power
Input
Output
Output
Output
Power
Power
Power
Output
14
TS#/48/24MHz
Output
15
GND48
Power
16
SEL 100/66#
Input
17
PD#
Input
18
CPU_STOP#
Input
19
VDD
Power
20
PCI-Stop#
Input
21
22
23,24
25
GND
GNDL
CPUCLK(1:0)
VDDL
Power
Power
Output
Power
26
SPREAD#
Output
27
REF0/SEL48#
Output
28
VDDREF
Power
Ground for 14.318 MHz reference clock outputs
14.318 MHz crystal input
14.318 MHz crystal output
3.3 V free running PCI clock output, will not be stopped by the PCI_STOP#
3.3 V PCI clock outputs, generating timing requirements for Pentium II Ground for PCI clock outputs
3.3 V power for the PCI clock outputs
3.3 V power for 48/24 MHz clocks
3.3 V 48 MHz clock output, fixed frequency clock typically used with USB devices
3.3 V 48 or 24 MHz output and Tri-state option, active low = tri state mode for testing,
active high = normal operation
Ground for 48/24 MHz clocks
control for the frequency of clocks at the CPU & PCICLK output pins. If logic "0" is
used the 66.6 MHz frequency is selected. If Logic "1" is used, the 100 MHz
frequency is selected. The PCI clock is multiplexed to run at 33.3 MHz for both
selected cases.
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.
Asynchronous active low input pin used to stop the CPUCLK in active low state, all
other clocks will continue to run. The CPUCLK will have a "Turnon " latency of at
least 3 CPU clocks.
Isolated 3.3 V power for core
Synchronous active low input used to stop the PCICLK in active low state. It will not
effect PCICLK_F or any other outputs.
Isolated ground for core
Ground for CPU clock outputs
2.5 V CPU clock outputs
2.5 V power for CPU clock outputs
Power-on spread spectrum enable option. Active low = spread spectrum clocking
enable. Active high = spread spectrum clocking disable.
3.3 V 14.318 MHz reference clock output and power-on 48/24 MHz select option.
Active low = 48 MHz output at pin 14. Active high = 24 MHz output at pin 14.
3.3 V power for 14.318 MHz reference clock outputs.
2
ICS9248-56
Select Functions
(Functionality determined by TS# and SEL100/66# pin, see below)
Functionality
PCI,
PCI_F
CPUCLK
REF0
Tristate
HI - Z
HI - Z
HI - Z
Testmode
TCLK/21
TCLK/61
TCLK1
Notes:
1. TCLK is a test clock driven on the X1 (crystal in pin) input during test mode.
SEL 100/66#
TS#
Function
0
0
Tri-State
0
-
(Reserved)
0
-
(Reserved)
0
1
Active 66.6MHz CPU, 33.3 PCI
1
0
Test Mode
1
-
(Reserved)
1
-
(Reserved)
1
1
Active 100MHz CPU, 33.3 PCI
Power Management
Clock Enable Configuration
C P U _ S TO P # P C I _ S TO P #
X
X
0
0
0
1
1
0
1
1
P W R _ DW N #
0
1
1
1
1
CPUCLK
L ow
Low
Low
100/66.6MHz
100/66.6MHz
PCICLK PCICLK_F
L ow
L ow
Low
33.3MHz
33.3 MHz 33.3MHz
Low
33.3MHz
33.3 MHz 33.3MHz
REF
Stopped
Running
Running
Running
Running
Crystal
O ff
Running
Running
Running
Running
VCOs
O ff
Running
Running
Running
Running
Full clock cycle timing is guaranteed at all times after the system has initially powered up except where noted. During power
up and power down operations using the PD# pin will not cause clocks of a short or longer pulse than that of the running clock.
The first clock pulse coming out of a stopped clock condition may be slightly distorted due to clock network charging circuitry.
Board routing and signal loading may have a large impact on the initial clock distortion also.
ICS9248-56 Power Management Requirements
SIGNAL
SIGNAL STATE
C P U _ S TO P #
0 (Disabled)2
1 (Enabled)1
0 (Disabled)2
1 (Enabled)1
1 (Normal Operation)3
0 (Power Down)4
P C I _ S TO P #
PD#
L a t e n cy
No. of rising edges of free running
PCICLK
1
1
1
1
3ms
2max
Notes.
1. Clock on latency is defined from when the clock enable goes active to when the first valid clock comes out of the device.
2. Clock off latency is defined from when the clock enable goes inactive to when the last clock is driven low out of the device.
3. Power up latency is when PD# goes inactive (high) to when the first valid clocks are output by the device.
4. Power down has controlled clock counts applicable to CPUCLK, PCICLK only.
The REF will be stopped independant of these.
3
ICS9248-56
CPU_STOP# Timing Diagram
CPUSTOP# is an asychronous input to the clock synthesizer. It is used to turn off the CPUCLKs for low power operation.
CPU_STOP# is synchronized by the ICS9248-56. The minimum that the CPUCLK is enabled (CPU_STOP# high pulse) is 100
CPUCLKs. All other clocks will continue to run while the CPUCLKs are disabled. The CPUCLKs will always be stopped in a low
state and start in such a manner that guarantees the high pulse width is a full pulse. CPUCLK on latency is less than 4 CPUCLKs
and CPUCLK off latency is less than 4 CPUCLKs.
Notes:
1. All timing is referenced to the internal CPUCLK.
2. CPU_STOP# is an asynchronous input and metastable conditions may exist.
This signal is synchronized to the CPUCLKs inside the ICS9248-56.
3. All other clocks continue to run undisturbed.
4. PD# and PCI_STOP# are shown in a high (true) state.
PCI_STOP# Timing Diagram
PCI_STOP# is an asynchronous input to the ICS9248-56. It is used to turn off the PCICLK (0:4) clocks for low power operation.
PCI_STOP# is synchronized by the ICS9248-56 internally. The minimum that the PCICLK (0:4) clocks are enabled (PCI_STOP#
high pulse) is at least 10 PCICLK (0:4) clocks. PCICLK (0:4) clocks are stopped in a low state and started with a full high pulse
width guaranteed. PCICLK (0:4) clock on latency cycles are only one rising PCICLK clock off latency is one PCICLK clock.
Notes:
1. All timing is referenced to the Internal CPUCLK (defined as inside the ICS9248 device.)
2. PCI_STOP# is an asynchronous input, and metastable conditions may exist. This signal is required to be synchronized
inside the ICS9248.
3. All other clocks continue to run undisturbed.
4. PD# and CPU_STOP# are shown in a high (true) state.
4
ICS9248-56
PD# Timing Diagram
The power down selection is used to put the part into a very low power state without turning off the power to the part. PD# is
an asynchronous active low input. This signal is synchronized internally by the ICS9248-56 prior to its control action of
powering down the clock synthesizer. Internal clocks will not be running after the device is put in power down state. When PD#
is active (low) all clocks are driven to a low state and held prior to turning off the VCOs and the crystal oscillator. The power on
latency is guaranteed to be less than 3ms. The power down latency is less than three CPUCLK cycles. PCI_STOP# and
CPU_STOP# are don’t care signals during the power down operations.
Notes:
1. All timing is referenced to the Internal CPUCLK (defined as inside the ICS9248 device).
2. PD# is an asynchronous input and metastable conditions may exist. This signal is synchronized inside the ICS9248.
3. The shaded sections on the VCO and the Crystal signals indicate an active clock is being generated.
5
ICS9248-56
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 - Input/Supply/Common Output Parameters
TA = 0 - 70C; Supply Voltage VDD = VDDL = 3.3 V +/-5% (unless otherwise stated)
PARAMETER
SYMBOL
CONDITIONS
Input High Voltage
VIH
Input Low Voltage
VIL
Input High Current
IIH
VIN = VDD
VIN = 0 V; Inputs with no pull-up resistors
Input Low Current
IIL1
VIN = 0 V; Inputs with pull-up resistors
Input Low Current
IIL2
Operating
IDD3.3OP66 CL = 0 pF; Select @ 66MHz
Supply Current
IDD3.3OP100 CL = 0 pF; Select @ 100MHz
CL = 0 pF; With input address to Vdd or GND
Power Down
IDD3.3PD
Supply Current
VDD = 3.3 V;
Input frequency
Fi
1
Input Capacitance
CIN
Logic Inputs
CINX
X1 & X2 pins
1
Transition Time
Ttrans
To 1st crossing of target Freq.
Clk Stabilization1
TSTAB
From VDD = 3.3 V to 1% target Freq.
Skew1
TCPU-PCI
VT = 1.5 V;
MIN
2
VSS-0.3
-5
-200
TYP
0.1
2.0
-100
60
66
70
11
14.318
27
36
1.5
2.4
MAX UNITS
VDD+0.3
V
0.8
V
5
µA
µA
µA
180
mA
180
mA
600
µA
16
5
45
3
3
4
MHz
pF
pF
ms
ms
ns
1
Guaranteed by design, not 100% tested in production.
Electrical Characteristics - Input/Supply/Common Output Parameters
TA = 0 - 70C; Supply Voltage VDD = 3.3 V +/-5%, VDDL = 2.5 V +/-5% (unless otherwise stated)
PARAMETER
SYMBOL
CONDITIONS
MIN
Operating
IDD2.5OP66 CL = 0 pF; Select @ 66.8 MHz
Supply Current
IDD2.5OP100 CL = 0 pF; Select @ 100 MHz
Skew1
tCPU-PCI2
VT = 1.5 V; VTL = 1.25 V
1.5
1
Guaranteed by design, not 100% tested in production.
6
TYP
16
23
MAX
72
100
UNITS
mA
mA
3
4
ns
ICS9248-56
Electrical Characteristics - CPUCLK
TA = 0 - 70C; VDD = 3.3 V +/-5%, VDDL = 2.5 V +/-5%; CL = 10 - 20 pF (unless otherwise stated)
PARAMETER
SYMBOL
CONDITIONS
MIN
Output High Voltage
VOH2B
IOH = -12.0 mA
1.8
Output Low Voltage
VOL2B
IOL = 12 mA
Output High Current
IOH2B
VOH = 1.7 V
Output Low Current
IOL2B
VOL = 0.7 V
27
1
Rise Time
tr2B
VOL = 0.4 V, VOH = 2.0 V
0.4
1
VOH = 2.0 V, VOL = 0.4 V
0.4
Fall Time
tf2B
VT = 1.25 V
44
Duty Cycle
dt2B1
1
VT = 1.25 V
Skew
tsk2B
tjcyc-cyc2B1 VT = 1.25 V
Jitter
VT = 1.25 V
tj1s2B1
1
tjabs2B
VT = 1.25 V
-250
TYP
2.3
0.31
MAX
1.15
1.4
48
134
186
52
150
1.6
1.6
55
175
250
150
+250
TYP
3.3
0.1
MAX
0.4
-22
57
UNITS
V
V
mA
mA
0.4
-27
UNITS
V
V
mA
mA
ns
ns
%
ps
ps
ps
ps
1
Guaranteed by design, not 100% tested in production.
Electrical Characteristics - PCICLK
TA = 0 - 70C; VDD = VDDL = 3.3 V +/-5%; CL = 30 pF
PARAMETER
SYMBOL
IOH = -18 mA
Output High Voltage
VOH1
Output Low Voltage
VOL1
IOL = 9.4 mA
Output High Current
IOH1
VOH = 2.0 V
Output Low Current
IOL1
VOL = 0.8 V
Rise Time
1
MIN
2.1
16
tr1
VOL = 0.4 V, VOH = 2.4 V
1.6
2
ns
tf1
VOH = 2.4 V, VOL = 0.4 V
1.8
2
ns
dt1
VT = 1.5 V
50
55
%
Skew
tsk1
tjcyc-cyc1
VT = 1.5 V
VT = 1.5 V
222
186
500
500
ps
ps
Jitter
tj1s1
tjabs1
VT = 1.5 V
VT = 1.5 V
52
200
150
500
ps
ps
Fall Time
1
1
Duty Cycle
1
1
CONDITIONS
45
Guaranteed by design, not 100% tested in production.
7
ICS9248-56
Electrical Characteristics - REF/48MHz/24MHz
TA = 0 - 70C; VDD = VDDL = 3.3 V +/-5%; CL = 10 - 20 pF (unless otherwise stated)
PARAMETER
SYMBOL
CONDITIONS
Output High Voltage
VOH5
IOH = -12 mA
Output Low Voltage
VOL5
IOL = 9 mA
VOH = 2.0 V
Output High Current
IOH5
VOL = 0.8 V
Output Low Current
IOL5
Rise Time
Fall Time
1
1
Duty Cycle
Jitter1
Jitter1
1
MIN
2.6
16
TYP
3.1
0.17
-44
42
MAX
0.4
-22
UNITS
V
V
mA
mA
tr5
VOL = 0.4 V, VOH = 2.4 V
1.4
4
ns
tf5
VOH = 2.4 V, VOL = 0.4 V
1.1
4
ns
53
185
385
169
469
55
250
800
250
800
%
ps
ps
ps
ps
dt5
tj1σ5
tjabs5
tj1σ5
tjabs5
VT = 1.5 V
VT = 1.5 V, REF
VT = 1.5 V, REF
VT = 1.5 V, 48 MHz
VT = 1.5 V, 48 MHz
45
8
ICS9248-56
General Layout Precautions:
1) Use a ground plane on the top layer of the
PCB in all areas not used by traces.
2) Make all power traces and vias as wide as
possible to lower inductance.
Notes:
1 All clock outputs should have series
terminating resistor. Not shown in all
places to improve readibility of
diagram
2 Optional EMI capacitor should be
used on all CPU, SDRAM, and PCI
outputs.
3 Optional crystal load capacitors are
recommended.
Capacitor Values:
C1, C2 : Crystal load values determined by user
All unmarked capacitors are 0.01 F ceramic
9
ICS9248-56
SYMBOL
In Millimeters
In Inches
COMMON DIMENSIONS COMMON DIMENSIONS
MIN
MAX
MIN
MAX
A
-
A1
0.05
-
.002
-
A2
1.65
1.85
.065
.073
b
0.22
0.38
.009
.015
c
0.09
0.25
SEE VARIATIONS
D
2.00
.079
.0035
.010
SEE VARIATIONS
E
7.40
E1
5.00
5.60
0.65 BASIC
.197
.220
0.0256 BASIC
0.55
0.95
SEE VARIATIONS
.022
.037
SEE VARIATIONS
e
L
N
α
8.20
-
0°
.291
.323
8°
0°
8°
MIN
MAX
MIN
9.90
10.50
.390
.413
MO-150 JEDEC
Doc.# 10-0033
6/1/00 Rev B
VARIATIONS
D mm.
N
28
D (inch)
MAX
Ordering Information
ICS9248F-56
Example:
ICS XXXXy F - PPP
Pattern Number (2 or 3 digit number for parts with ROM code patterns)
Package Type
F=SSOP
Revision Designator
Device Type (consists of 3 or 4 digit numbers)
Prefix
ICS, AV = Standard Device
10
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.
ICS9248-56
SY MBOL
In Millimeters
COMMON DIMENSIONS
MIN
MA X
In Inches
COMMON DIMENSIONS
MIN
MA X
A
-
1.20
-
.047
A1
0.05
0.15
.002
.006
A2
0.80
1.05
.032
.041
b
0.19
0.30
.007
.012
c
0.09
0.20
SEE V A RIA TIONS
D
.0035
.008
SEE V A RIA TIONS
6.40 BA SIC
E
E1
4.30
e
4.50
0.252 BA SIC
.169
0.65 BA SIC
L
0.45
0.75
SEE V A RIA TIONS
N
α
aaa
.177
0.0256 BA SIC
.018
.030
SEE V A RIA TIONS
0°
8°
0°
8°
-
0.10
-
.004
MIN
MA X
MIN
9.60
9.80
V A RIA TIONS
D mm.
N
4.40 mm. Body, 0.65 mm. pitch TSSOP
(0.0256 mil)
(173 mil)
28
D (inch)
MA X
.378
.386
M O -1 53 J E D E C
7 / 6/ 00 R ev B
D o c . # 1 0-0 0 3 8
Ordering Information
ICS9248yG-56-T
Example:
ICS XXXX y G - PPP - T
Designation for tape and reel packaging
Pattern Number (2 or 3 digit number for parts with ROM code patterns)
Package Type
G=TSSOP
Revision Designator (will not correlate with datasheet revision)
Device Type (consists of 3 or 4 digit numbers)
Prefix
ICS, AV = Standard Device
11
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.