ICS ICS9248-127

Integrated
Circuit
Systems, Inc.
ICS9248-127
Frequency Generator & Integrated Buffers for PENTIUM/ProTM
General Description
Features
The ICS9248-127 is the single chip clock solution for Desktop
designs using the VIA MVP4 and Aladdin 7 style chipset. It
provides all necessary clock signals for such a system.
Spread spectrum may be enabled through I2C programming.
Spread spectrum typically reduces system EMI by 8dB to
10dB. This simplifies EMI qualification without resorting to
board design iterations or costly shielding. The ICS9248127 employs a proprietary closed loop design, which tightly
controls the percentage of spreading over process and
temperature variations.
•
•
•
•
•
Up to 124MHz frequency support.
Spread Spectrum for EMI control 0 to -0.5% down
spread and ±0.25% center spread
Serial I2C interface for Power Management,
Frequency Select, Spread Spectrum.
Provides the following system clocks
- 4-CPUs @ 3.3V, up to 124MHz.
- 13-SDRAMs @3.3V, up to 124MHz
(including SDRAM_F)
- 6-PCI (including 1 free running, PCICLK_F)
@3.3V, CPU/2 or CPU/3.
- 1-24MHz @3.3V fixed.
- 1-48MHz @3.3V fixed.
- 2-REF @3.3V, 14.318MHz.
Efficient Power management scheme through PCI
and STOP CLOCKS.
Block Diagram
48MHz
24MHz
/2
X1
X2
XTAL
OSC
2
REF (1:0)
BUFFER IN
CPUCLK_F
PLL1
Spread
Spectrum
FS(3:0)
MODE
4
STOP
STOP
LATCH
3
12
CPUCLK (2:0)
SDRAM (11:0)
SDRAM_F
4
POR
CLK_STOP#
PCI_STOP#
Control
Logic
SDATA
SCLK
PCI
CLOCK
DIVDER
STOP
5
PCICLK (4:0)
PCICLK_F
Config.
Pin Configuration
VDDREF
*PCI_STOP#/REF0
GND
X1
X2
VDDPCI
*MODE/PCICLK_F
*FS3/PCICLK0
GND
PCICLK1
PCICLK2
PCICLK3
PCICLK4
VDDPCI
BUFFER IN
GND
SDRAM11
SDRAM10
VDDSDR
SDRAM9
SDRAM8
GND
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
ICS9248-127
PLL2
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
REF1/FS2*
VDDCPU
CPUCLK_F
CPUCLK0
GND
CPUCLK1
CPUCLK2
CLK_STOP#
GND
SDRAM_F
SDRAM0
SDRAM1
VDDSDR
SDRAM2
SDRAM3
GND
SDRAM4
SDRAM5
VDDSDR
SDRAM6
SDRAM7
VDD48
48MHz/FS0*
24MHz/FS1*
Reg.
48-Pin SSOP
* Internal Pull-up Resistor of 240K to VDD
Power Groups
VDDCPU, GNDCPU = CPUCLKS, CPUCLK_F
VDDSDR, GNDSDR = SDRAMCLKS, SDRAM_F
VDDPCI, GNDPCI = PCICLKS, PCICLK_F
VDD48 = 48MHz, 24MHz
VDDREF, GNDREF = REF, X1, X2
9248-127 Rev C 8/18/00
Pentium is a trademark of Intel Corporation
I2C is a trademark of Philips 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.
ICS9248-127
Pin Descriptions
PIN NUMBER
P I N NA M E
1, 6, 14, 19, 27, 30,
VDD
36, 47
REF0
TYPE
PWR
OUT
2
PCI_STOP#1
3,9,16,22,
33,40,44
GND
IN
PWR
4
X1
IN
5
X2
OUT
PCICLK_F
OUT
7
8
13, 12, 11, 10
15
17, 18, 20, 21, 28,
29, 31, 32, 34, 35,
37, 38
23
24
25
26
MODE1, 2
IN
FS31
IN
PCICLK0
OUT
PCICLK (4:1)
OUT
BUFFER IN
SDRAM (11:0)
I/O
IN
24MHz
OUT
FS1
1, 2
48MHz
FS0
1, 2
SDRAM_F
41
CLK_STOP#
46
48
OUT
SDATA
SCLK
39
42, 43, 45
IN
IN
OUT
IN
OUT
DESCRIPTION
3.3V power supply
14.318 Mhz reference clock.This REF output is the STRONGER
buffer for ISA BUS loads
Halts PCICLK clocks at logic 0 level, when input low
(In mobile mode, MODE=0)
Ground
Crystal input, has internal load cap (36pF) and feedback
resistor from X2
Crystal output, nominally 14.318MHz.
Free running PCI clock not affected by PCI_STOP# for power
management.
pin 2 function select pin, 1=Desktop Mode, 0=Mobile Mode.
Latched Input.
Frequency select pin. Latched Input.
PCI clock outputs. Syncheronous to CPU clocks with 1-4ns skew
(CPU early)
PCI clock outputs. Syncheronous to CPU clocks with 1-4ns skew
(CPU early)
Input to Fanout Buffers for SDRAM outputs.
SDRAM clock outputs, Fanout Buffer outputs from BUFFER IN pin
(controlled by chipset).
Data pin for I2C circuitry 5V tolerant
Clock pin of I2C circuitry 5V tolerant
24MHz output clock
Frequency select pin. Latched Input.
48MHz output clock
Frequency select pin. Latched Input
CPUCLK (2:0)
OUT
Free running SDRAM clock output. Not affected by CPU_STOP#
This asynchronous input halts CPUCLK & SDRAM at logic "0"
level when driven low.
CPU clock outputs, powered by VDDCPU
CPUCLK_F
REF1
FS21, 2
OUT
OUT
IN
Free running CPU clock. Not affected by the CPU_STOP#
14.318 MHz reference clock.
Frequency select pin. Latched Input
IN
Notes:
1: Internal Pull-up Resistor of 240K to 3.3V on indicated inputs
2: Bidirectional input/output pins, input logic levels are latched at internal power-on-reset. Use 10Kohm resistor to
program logic Hi to VDD or GND for logic low.
2
ICS9248-127
Mode Pin - Power Management Input Control
MODE
(Latched Input)
Pin 2
PCI_STOP#
(Input)
REF0
(Output)
0
1
Functionality
VDD1,2,3 = 3.3V±5%, TA=0 to 70°C
Crystal (X1, X2) = 14.31818MHz
FS3
FS2
FS1
FS0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
CPU
(MHz)
124.00
120.00
114.99
109.99
105.00
83.31
80.00
75.00
100.00
95.19
83.31
97.00
90.00
70.00
66.82
60.00
PCI
(MHz)
41.33
40.00
38.33
36.66
35.00
41.65
40.00
37.50
33.33
31.73
27.77
32.33
30.00
35.00
33.41
30.00
3
ICS9248-127
Serial Configuration Command Bitmap
Byte0: Functionality and Frequency Select Register (default = 0)
Bit
Bit 7
Bit
[2, 6:4]
Bit 3
Bit 1
Bit 0
Description
0 - ±0.25% Center Spread Spectrum Modulation
1 - 0 to -0.5% Down Spread Spectrum Modulation
CPUCLK
PCICLK
Bit [2, 6:4]
(MHz)
(MHz)
0000
124.00
41.33
0001
120.00
40.00
0010
114.99
38.33
0011
109.99
36.66
0100
105.00
35.00
0101
83.31
41.65
0110
80.00
40.00
0111
75.00
37.50
1000
100.00
33.33
1001
95.19
31.73
1010
83.31
27.77
1011
97.00
32.33
1100
90.00
30.00
1101
70.00
35.00
1110
66.82
33.41
1111
60.00
30.00
0 - Frequency is selected by hardware select, latched inputs
1 - Frequency is selected by Bit [2, 6:4]
0 - Normal
1 - Spread Spectrum Enabled
0 - Running
1- Tristate all outputs
PWD
1
Note1
0,010
0
Note 2
1
0
Note 1. Default at Power-up will be for latched logic inputs to define frequency.
I2C readback of the power up default indicate the revision ID code in bit 2,
6:4 as shown.
Note 2. To ensure normal operation, Bit 7 needs to be "0" when in non - spread spectrum
mode (Bit 1 = 0).
Note: PWD = Power-Up Default.
I2C is a trademark of Philips Corporation
4
ICS9248-127
Byte 1: CPU, Active/Inactive Register (1 = enable, 0 = disable)
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Pin #
46
39
42
43
45
PWD
X
1
1
1
1
1
1
1
Description
Latched FS2#
CPUCLK_F (Act/Inact)
(Reserved)
(Reserved)
SDRAM_F (Act/Inact)
CPUCLK2 (Act/Inact)
CPUCLK1 (Act/Inact)
CPUCLK0 (Act/Inact)
Byte 2: PCI Active/Inactive Register (1 = enable, 0 = disable)
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Pin #
7
13
12
11
10
8
PWD
X
1
1
1
1
1
1
1
Description
Latched FS0#
PCICLK_F (Act/Inact)
(Reserved)
PCICLK4 (Act/Inact)
PCICLK3 (Act/Inact)
PCICLK2 (Act/Inact)
PCICLK1 (Act/Inact)
PCICLK0 (Act/Inact)
Byte 3: SDRAM Active/Inactive Register (1 = enable, 0 = disable)
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Pin #
17
18
20
21
28
29
31
32
PWD
1
1
1
1
1
1
1
1
Description
SDRAM11 (Active/Inactive)
SDRAM10 (Active/Inactive)
SDRAM9 (Active/Inactive)
SDRAM8 (Active/Inactive)
SDRAM7 (Active/Inactive)
SDRAM6 (Active/Inactive)
SDRAM5 (Active/Inactive)
SDRAM4 (Active/Inactive)
Notes:
1. Inactive means outputs are held LOW and are disabled from switching.
2. Latched Frequency Selects (FS#) will be inverted logic load of the input frequency select pin conditions.
5
ICS9248-127
Byte 4: Reserved Active/Inactive Register (1 = enable, 0 = disable)
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Pin #
-
PWD
1
1
1
1
X
1
X
1
Description
(Reserved)
(Reserved)
(Reserved)
(Reserved)
Latched FS1#
(Reserved)
Latched FS3#
(Reserved)
Byte 5: Peripheral Active/Inactive Register (1 = enable, 0 = disable)
Bit
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Pin #
34
35
37
38
26
25
48
2
PWD
1
1
1
1
1
1
1
1
Description
SDRAM3 (Act/Inact)
SDRAM2 (Act/Inact)
SDRAM1 (Act/Inact)
SDRAM0 (Act/Inact)
48MHz (Act/Inact)
24MHz (Act/Inact)
REF1 (Act/Inact)
REF0 (Act/Inact)
Notes:
1. Inactive means outputs are held LOW and are disabled from switching.
2. Latched Frequency Selects (FS#) will be inverted logic load of the input frequency select pin conditions.
6
ICS9248-127
Absolute Maximum Ratings
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . .
Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ambient Operating Temperature . . . . . . . . . . . .
Case Temperature . . . . . . . . . . . . . . . . . . . . . . . .
Storage Temperature . . . . . . . . . . . . . . . . . . . . . .
5.5 V
GND –0.5 V to VDD +0.5 V
0°C to +70°C
115°C
–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
T A = 0 - 70C; Supply Voltage VDD = 3.3 V +/-5% (unless otherwise stated)
PARAM ETER
Input High Voltage
Input Low Voltage
Supply Current
Input frequency
Input Capacitance 1
Transition Time 1
Settling Time
1
Clk Stabilization
Skew 1
1
1
SYM BOL
VIH
VIL
IDD3 .3
Fi
C IN
C INX
T tran s
CONDITIONS
C L = 0 pF; Select @ 66M
VDD = 3.3 V;
Logic Inputs
X1 & X2 pins
M IN
2
VSS -0.3
27
To 1st crossing of target Freq.
Ts
From 1st crossing to 1% target Freq.
T STAB
T CPU-BUS
From VDD = 3.3 V to 1% target Freq.
VT = 1.5 V;
Guarenteed by design, not 100% tested in production.
7
TYP
MAX UNITS
VDD+0.3
V
0.8
V
77
180
mA
14.318
M Hz
5
pF
36
45
pF
1.5
3
ms
ms
1.0
2.2
3
ms
4.0
ns
ICS9248-127
Electrical Characteristics - CPU
T A = 0 - 70C; VDD=3.3V +/-5%; CL = 20 pF (unles s otherwis e s pecified)
PA RA M ETER
SYM BOL
Output Impedance
RD SP 2 B
Output Impedance
Output High Voltage
Output Low Voltage
Output High Current
Output Low Current
Ris e Time
Fall Time
1
1
Duty Cycle
1
Skew window
1
Jitter, Cycle-to-cycle
1
1
1
CONDITIONS
M IN
TYP
M A X UNITS
Vo=VD D *(0.5)
10
20
Ω
Vo=VD D *(0.5)
IO H = -12 mA
IO L = 12 mA
VO H = 1.7 V
VO L = 0.7 V
10
2.0
20
Ω
V
V
mA
mA
t r2 B
RD SN 2 B
VO H 2 B
VO L 2 B
IO H 2 B
IO L 2 B
1
0.4
-19
19.0
2.3
0.2
-41
37.0
VO L = 0.4 V, VO H = 2.4 V
0.4
1.28
2.0
ns
t f2 B
VO H = 2.4 V, VO L = 0.4 V
0.4
1.49
2.0
ns
d t2B
VT = 1.5 V
48.0
54.8
58.0
%
t sk 2 B
VT = 1.5 V
222
250
ps
t jcyc-cy c2 B
VT = 1.5 V
152
250
ps
Guaranteed by des ign, not 100% tes ted in production.
Electrical Characteristics - 24MHz, 48MHz, REF
T A = 0 - 70C; VD D =3.3V +/-5%; CL = 20 pF (unles s otherwis e s pecified)
PA RA M ETER
Output Impedance
Output Impedance
Output High Voltage
Output Low Voltage
Output High Current
Output Low Current
Ris e Time
Fall Time
1
1
Duty Cycle
1
Jitter
1
1
SYM BOL
RD SP 5
1
RD SN 5
VO H 5
VO L 5
IO H 5
IO L 5
1
CONDITIONS
M IN
TYP
M A X UNITS
Vo=VD D *(0.5)
20
60
Ω
Vo=VD D *(0.5)
IO H = -14 mA
IO L = 6.0 mA
VO H = 2.0 V
VO L = 0.8 V
20
2.4
60
Ω
V
V
mA
mA
10
2.9
0.25
-42
18
0.4
-20
t r5
VO L = 0.4 V, VO H = 2.4 V
1.74
4.0
ns
t f5
VO H = 2.4 V, VO L = 0.4 V
2.05
4.0
ns
d t5
VT = 1.5 V,
53.2
55
%
t jab s5
VT = 1.5 V
307
800
ps
45
Guaranteed by des ign, not 100% tes ted in production.
8
ICS9248-127
Electrical Characteristics - PCI
TA = 0 - 70C; VDD=3.3V +/-5%; CL = 30 pF (unless otherwise specified)
PARAMETER
SYMBOL
CONDITIONS
Output Impedance
RDSP1
Output Impedance
Output High Voltage
Output Low Voltage
Output High Current
Output Low Current
RDSN1
VOH1
VOL1
IOH1
IOL1
TYP
Vo=VDD*(0.5)
12
23
55
Ω
Vo=VDD*(0.5)
IOH = -18 mA
IOL = 9.4 mA
VOH = 2.0 V
VOL = 0.8 V
12
2.4
20
2.9
0.2
-58
52
55
Ω
V
V
mA
mA
25
MAX UNITS
0.4
-22
tr1
VOL = 0.4 V, VOH = 2.4 V
1.38
2.0
ns
1
tf1
dt1
VOH = 2.4 V, VOL = 0.4 V
1.65
2.0
ns
51.1
55
%
VT = 1.5 V
236
500
ps
VT = 1.5 V
214
500
ps
1
Duty Cycle
Skew window1
VT = 1.5 V
tsk1
tjabs1
Jitter
1
1
MIN
1
Rise Time
Fall Time
1
1
45
Guaranteed by design, not 100% tested in production.
Electrical Characteristics - SDRAM
T A = 0 - 70C; VD D =3.3V +/-5%; CL = 30 pF (unless otherwise specified)
PA RA M ETER
SYM BOL
Output Impedance
RD SP 2A
Output Impedance
Output High Voltage
Output Low Voltage
Output High Current
Output Low Current
Ris e Time
Fall Time
1
Duty Cycle
1
Skew W indow
1
1
Skew (Buffer-In to SDRA M )
1
CONDITIONS
M IN
Vo=VD D *(0.5)
10
Vo=VD D *(0.5)
IO H = -28 mA
IO L = 19 mA
VO H = 2.0 V
VO L = 0.8 V
10
2.4
t r2A
RD SN 2A
VO H 2A
VO L2A
IO H 2A
IO L 2A
1
1
1
TYP
M A X UNITS
20
Ω
20
Ω
V
V
mA
mA
0.4
-42
33
2.8
0.3
-72
50
VO L = 0.4 V, VO H = 2.4 V
0.5
0.97
1.6
ns
t f2A
VO H = 2.4 V, VO L = 0.4 V
0.5
1.07
1.6
ns
d t2A
VT = 1.5 V
45
49.1
55
%
t sk2A
VT = 1.5 V
145
250
ps
t sk2A
VT = 1.5 V
3.5
5
ps
Guaranteed by design, not 100% tested in production.
9
ICS9248-127
General I2C serial interface information
The information in this section assumes familiarity with I2C programming.
For more information, contact ICS for an I2C programming application note.
How to Write:
How to Read:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Controller (host) sends a start bit.
Controller (host) sends the write address D2 (H)
ICS clock will acknowledge
Controller (host) sends a dummy command code
ICS clock will acknowledge
Controller (host) sends a dummy byte count
ICS clock will acknowledge
Controller (host) starts sending first byte (Byte 0)
through byte 5
• ICS clock will acknowledge each byte one at a time.
• Controller (host) sends a Stop bit
Controller (host) will send start bit.
Controller (host) sends the read address D3 (H)
ICS clock will acknowledge
ICS clock will send the byte count
Controller (host) acknowledges
ICS clock sends first byte (Byte 0) through byte 5
Controller (host) will need to acknowledge each byte
Controller (host) will send a stop bit
How to Write:
Controller (Host)
Start Bit
Address
D2(H)
ICS (Slave/Receiver)
How to Read:
Controller (Host)
Start Bit
Address
D3(H)
ACK
Dummy Command Code
ACK
ICS (Slave/Receiver)
ACK
Byte Count
Dummy Byte Count
ACK
ACK
ACK
ACK
ACK
ACK
ACK
ACK
ACK
ACK
ACK
ACK
ACK
ACK
Stop Bit
Byte 0
Byte 0
Byte 1
Byte 1
Byte 2
Byte 2
Byte 3
Byte 3
Byte 4
Byte 4
Byte 5
Byte 5
Stop Bit
Notes:
1.
2.
3.
4.
5.
6.
The ICS clock generator is a slave/receiver, I2C component. It can read back the data stored in the latches for
verification. Read-Back will support Intel PIIX4 "Block-Read" protocol.
The data transfer rate supported by this clock generator is 100K bits/sec or less (standard mode)
The input is operating at 3.3V logic levels.
The data byte format is 8 bit bytes.
To simplify the clock generator I2C interface, the protocol is set to use only "Block-Writes" from the controller. The
bytes must be accessed in sequential order from lowest to highest byte with the ability to stop after any complete byte
has been transferred. The Command code and Byte count shown above must be sent, but the data is ignored for those
two bytes. The data is loaded until a Stop sequence is issued.
At power-on, all registers are set to a default condition, as shown.
10
ICS9248-127
Shared Pin Operation Input/Output Pins
Figure 1 shows a means of implementing this function when
a switch or 2 pin header is used. With no jumper is installed
the pin will be pulled high. With the jumper in place the pin
will be pulled low. If programmability is not necessary, than
only a single resistor is necessary. The programming resistors
should be located close to the series termination resistor to
minimize the current loop area. It is more important to locate
the series termination resistor close to the driver than the
programming resistor.
The I/O pins designated by (input/output) on the ICS9248127 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 5-bit internal data latch. At the end of Power-On reset,
(see AC characteristics for timing values), the device changes
the mode of operations for these pins to an output function.
In this mode the pins produce the specified buffered clocks
to external loads.
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.
Via to
VDD
Programming
Header
2K Via to Gnd
Device
Pad
8.2K Clock trace to load
Series Term. Res.
Fig. 1
11
ICS9248-127
CLK_STOP# Timing Diagram
CLK_STOP# is an asychronous input to the clock synthesizer. It is used to turn off the CPU clocks for low power operation.
CLK_STOP# is synchronized by the ICS9248-127. The minimum that the CPU clock is enabled (CPU_STOP# high pulse) is
100 CPU clocks. All other clocks will continue to run while the CPU clocks are disabled. The CPU clocks will always be
stopped in a low state and start in such a manner that guarantees the high pulse width is a full pulse. CPU clock on latency is
less than 4 CPU clocks and CPU clock off latency is less than 4 CPU clocks.
INTERNAL
CPUCLK
PCICLK
CLK_STOP#
PCI_STOP# (High)
IOAPIC
SDRAM
CPUCLK
CPUCLK _F
SDRAM_F
Notes:
1. All timing is referenced to the internal CPU clock.
2. CLK_STOP# is an asynchronous input and metastable conditions may exist. This signal is synchronized
to the CPU clocks inside the ICS9248-127.
3. IOAPIC output is Stopped Glitch Free by CPUSTOP# going low.
4. SDRAM-F output is controlled by Buffer in signal, not affected by the ICS9248-127
CLK_STOP# signal. SDRAM (0:11) are controlled as shown.
5. All other clocks continue to run undisturbed.
12
ICS9248-127
PCI_STOP# Timing Diagram
PCI_STOP# is an asynchronous input to the ICS9248-127. It is used to turn off the PCICLK [4:0] clocks for low power
operation. PCI_STOP# is synchronized by the ICS9248-127 internally. The minimum that the PCICLK [4:0] clocks are
enabled (PCI_STOP# high pulse) is at least 10 PCICLK [4:0] clocks. PCICLK [4:0] clocks are stopped in a low state and started
with a full high pulse width guaranteed. PCICLK [4:0] clock on latency cycles are only one rising PCICLK clock off latency
is one PCICLK clock.
CPUCLK
(Internal)
PCICLK_F
(Internal)
PCICLK_F
(Free-running)
CPU_STOP#
PCI_STOP#
PCICLK
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. CPU_STOP# is shown in a high (true) state.
13
ICS9248-127
SYMBOL
In Millimeters
COMMON DIMENSIONS
MIN
MAX
In Inches
COMMON DIMENSIONS
MIN
MAX
A
2.413
2.794
.095
A1
0.203
0.406
.008
.016
b
0.203
0.343
.008
.0135
c
D
0.127
0.254
SEE VARIATIONS
.005
.010
SEE VARIATIONS
E
10.033
10.668
.395
.420
E1
7.391
7.595
.291
.299
e
0.635 BASIC
h
0.381
L
0.508
1.016
SEE VARIATIONS
N
α
0.635
0°
.110
0.025 BASIC
.015
.025
.020
.040
SEE VARIATIONS
8°
0°
8°
MIN
MAX
MIN
MAX
28
9.398
9.652
.370
.380
34
11.303
11.557
.445
.455
48
15.748
16.002
.620
.630
56
18.288
18.542
.720
.730
64
20.828
21.082
.820
.830
VARIATIONS
N
D mm.
D (inch)
Ordering Information
ICS9248yF-127-T
Example:
ICS XXXX y F - PPP - T
Designation for tape and reel packaging
Pattern Number (2 or 3 digit number for parts with ROM code patterns)
Package Type
F=SSOP
Revision Designator (will not correlate with datasheet revision)
Device Type (consists of 3 or 4 digit numbers)
Prefix
ICS, AV = Standard Device
14
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.