ICS ICS952621

ICS952621
Integrated
Circuit
Systems, Inc.
Programmable Timing Control Hub™ for Next Gen P4™ processor
Recommended Application:
CK409 48-pin part
Output Features:
•
2 - 0.7V current-mode differential CPU pairs
•
1 - 0.7V current-mode differential CPU pairs for ITP
•
1 - 0.7V current-mode differential SRC pair
•
9 - PCI (33MHz), including 3 free running PCI
•
1 - USB, 48MHz
•
1 - DOT, 48MHz
•
2 - REF, 14.318MHz
•
3 - 3V66, 66.66MHz
•
Supports CPU clks up to 400MHz in test mode
•
Uses external 14.318MHz crystal
•
Supports undriven differential CPU, SRC pair in PD#
and CPU_STOP# for power management.
1 - 3V66/VCH, selectable 48MHz or 66MHz
Key Specifications:
•
CPU/SRC outputs cycle-cycle jitter < 125ps
•
3V66 outputs cycle-cycle jitter < 250ps
•
PCI outputs cycle-cycle jitter < 250ps
•
CPU outputs skew: < 100ps
•
+/- 300ppm frequency accuracy on CPU & SRC clocks
Functionality
USB/
FS2
DOT
CPU
SRC
3V66 PCI
REF
MHz
B6b5 FS_A FS_B MHz
MHz
MHz MHz
MHz
0
0
100.00 100/200 66.66 33.33 14.318 48.00
0
1
200.00 100/200 66.66 33.33 14.318 48.00
0
1
0
133.33 100/200 66.66 33.33 14.318 48.00
1
1
166.66 100/200 66.66 33.33 14.318 48.00
0
0
200.00 100/200 66.66 33.33 14.318 48.00
0
1
400.00 100/200 66.66 33.33 14.318 48.00
1
1
0
266.66 100/200 66.66 33.33 14.318 48.00
1
1
333.33 100/200 66.66 33.33 14.318 48.00
Pin Configuration
FS_A/REF1
FS_B/REF0
VDDREF
X1
X2
GND
PCICLK_F0
PCICLK_F1
PCICLK_F2
VDDPCI
GND
PCICLK0
PCICLK1
PCICLK2
PCICLK3
VDDPCI
GND
PCICLK4
PCICLK5
PD#
48MHz_DOT
48MHz_USB
GND
VDD48
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
ICS952621
•
Features/Benefits:
•
Supports tight ppm accuracy clocks for Serial-ATA
•
Supports spread spectrum modulation, 0 to -0.5%
down spread and +/- 0.25% center spread
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
VDDA
GND
IREF
CPUCLKT_ITP
CPUCLKC_ITP
GND
CPUCLKT1
CPUCLKC1
VDDCPU
CPUCLKT0
CPUCLKC0
GND
SRCCLKT
SRCCLKC
VDD
VttPWR_GD#
SDATA
SCLK
3V66_0
3V66_1
GND
VDD3V66
3V66_2
3V66_3/VCH
**120KΩ pull-down
48-pin SSOP
0756A—09/10/04
ICS952621
Integrated
Circuit
Systems, Inc.
Pin Description
PIN
#
PIN NAME
PIN TYPE
1
FS_A/REF1
I/O
2
FS_B/REF0
I/O
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
VDDREF
X1
X2
GND
PCICLK_F0
PCICLK_F1
PCICLK_F2
VDDPCI
GND
PCICLK0
PCICLK1
PCICLK2
PCICLK3
VDDPCI
GND
PCICLK4
PCICLK5
PWR
IN
OUT
PWR
OUT
OUT
OUT
PWR
PWR
OUT
OUT
OUT
OUT
PWR
PWR
OUT
OUT
20
PD#
IN
21
22
23
24
48MHz_DOT
48MHz_USB
GND
VDD48
OUT
OUT
PWR
PWR
25
3V66_3/VCH
OUT
26
27
28
29
30
31
32
3V66_2
VDD3V66
GND
3V66_1
3V66_0
SCLK
SDATA
OUT
PWR
PWR
OUT
OUT
IN
I/O
33
VttPWR_GD#
IN
34
VDD
OUT
35
SRCCLKC
OUT
36
SRCCLKT
OUT
37
GND
PWR
38
CPUCLKC0
OUT
39
CPUCLKT0
OUT
40
VDDCPU
PWR
41
CPUCLKC1
OUT
42
CPUCLKT1
OUT
43
GND
PWR
44
CPUCLKC_ITP
OUT
45
CPUCLKT_ITP
OUT
46
IREF
OUT
47
48
GND
VDDA
PWR
PWR
DESCRIPTION
FS_A latched input for frequency select
Reference output, 14.318Hz
FS_B latched input for frequency select
Reference output, 14.318Hz
Ref, XTAL power supply, nominal 3.3V
Crystal input, Nominally 14.318MHz.
Crystal output, Nominally 14.318MHz
Ground pin.
Free running PCI clock not affected by PCI_STOP# .
Free running PCI clock not affected by PCI_STOP# .
Free running PCI clock not affected by PCI_STOP# .
Power supply for PCI clocks, nominal 3.3V
Ground pin.
PCI clock output.
PCI clock output.
PCI clock output.
PCI clock output.
Power supply for PCI clocks, nominal 3.3V
Ground pin.
PCI clock output.
PCI clock output.
Asynchronous active low input pin, with 120Kohm internal pull-up resistor, used
to power down the device. The internal clocks are disabled and the VCO and
the crystal are stopped.
48.008MHz Dot clock output
48.008MHz USB clock output
Ground pin.
Power for 48MHz output buffers and fixed PLL core.
3.3V 66.66MHz clock output
VCH: 48MHz VCH clock output
3.3V 66.66MHz clock output
Power pin for the 3V66 clocks.
Ground pin.
3.3V 66.66MHz clock output
3.3V 66.66MHz clock output
Clock pin of SMBus circuitry, 5V tolerant.
Data pin for SMBus circuitry, 5V tolerant.
This 3.3V LVTTL input is a level sensitive strobe used to determine when latch
inputs are valid and are ready to be sampled. This is an active low input.
Power supply, nominal 3.3V
Complementary clock of differential pair for S-ATA support.
+/- 300ppm accuracy required.
True clock of differential pair for S-ATA support.
+/- 300ppm accuracy required.
Ground pin.
Complementary clock of differential pair CPU outputs. These are current mode
outputs. External resistors are required for voltage bias.
True clock of differential pair CPU outputs. These are current mode outputs.
External resistors are required for voltage bias.
Supply for CPU clocks, 3.3V nominal
Complementary clock of differential pair CPU outputs. These are current mode
outputs. External resistors are required for voltage bias.
True clock of differential pair CPU outputs. These are current mode outputs.
External resistors are required for voltage bias.
Ground pin.
"Complementary" clocks of differential pair CPU outputs for ITP.. These are
current mode outputs. External resistors are required for voltage bias.
"True" clocks of differential pair CPU outputs for ITP. These are current mode
outputs. External resistors are required for voltage bias.
This pin establishes the reference current for the differential current-mode
output pairs. This pin requires a fixed precision resistor tied to ground in order
to establish the appropriate current. 475 ohms is the standard value.
Ground pin.
3.3V power for the PLL core.
0756A—09/10/04
2
ICS952621
Integrated
Circuit
Systems, Inc.
General Description
ICS962621 is a programmable 48 pin clock chip following Intel CK409 Yellow Cover specification. This clock synthesizer provides a single
chip solution for next generation P4 Intel processors and Intel chipsets. ICS962621 is driven with a 14.318MHz crystal. It generates CPU
outputs up to 200MHz. It also provides a tight ppm accuracy output for Serial ATA support.
Block Diagram
PLL2
X1
X2
Frequency
Dividers
48MHz, USB, DOT, VCH
XTAL
REF (1:0)
CPUCLKT (1:0)
CPUCLKC (1:0)
SRCCLKT0
Programmable
Spread
PLL1
SCLK
SDATA
Programmable
Frequency
Dividers
STOP
Logic
SRCCLKC0
3V66(3:0)
PCICLK (5:0), PCICLK_F (2:0)
VTTPWRGD#
Control
Logic
PD#
CPUCLKT_ITP
FS_A
CPUCLKC_ITP
FS_B
I REF
MODE
RESET#
Power Groups
Pin Number
Description
VDD
3
27
10,16
34
48
24
--
GND
6
28
11,17
37
47
23
47
Xtal, Ref
3V66 [0:3]
PCICLK outputs
SRCCLK outputs
Master clock, CPU Analog
48MHz, Fix Digital, Fix Analog
IREF
40
43
CPUCLK clocks
0756A—09/10/04
3
ICS952621
Integrated
Circuit
Systems, Inc.
Absolute Max
Symbol
VDD_A
VDD_In
Ts
Tambient
Tcase
ESD prot
Parameter
3.3V Core Supply Voltage
3.3V Logic Input Supply Voltage
Storage Temperature
Ambient Operating Temp
Case Temperature
Input ESD protection
human body model
Min
Max
VDD + 0.5V
VDD + 0.5V
150
70
115
-0.5
-65
0
Units
V
V
°C
°C
°C
2000
V
Electrical Characteristics - Input/Supply/Common Output Parameters
TA = 0 - 70°C; Supply Voltage VDD = 3.3 V +/-5%
PARAMETER
SYMBOL
CONDITIONS
MIN
Input High Voltage
VIH
3.3V +/-5%
Input Low Voltage
VIL
3.3V +/-5%
Input High Current
IIH
VIN = VDD
VIN = 0 V; Inputs with no pull-up
resistors
VIN = 0 V; Inputs with pull-up
resistors
2
VSS 0.3
-5
IIL1
Input Low Current
IIL2
Operating Supply Current
IDD3.3OP
Full Active, CL = Full load;
Powerdown Current
IDD3.3PD
Input Frequency3
Pin Inductance1
Fi
Lpin
CIN
COUT
CINX
all diff pairs driven
all differential pairs tri-stated
VDD = 3.3 V
TYP
MAX
VDD + 0.3
V
0.8
V
5
uA
-5
uA
-200
uA
260
0.3
350
mA
35
12
mA
mA
MHz
nH
pF
pF
pF
3
1
1
1
1
ms
1,2
kHz
1
us
1
ns
ns
1
2
14.31818
7
5
6
5
Logic Inputs
Output pin capacitance
X1 & X2 pins
From
VDD
Power-Up or deTSTAB
1.8
Clk Stabilization1,2
assertion of PD# to 1st clock.
Modulation Frequency
Triangular Modulation
30
33
CPU output enable after
Tdrive_PD#
300
PD# de-assertion
Tfall_Pd#
PD# fall time of
5
Trise_Pd#
PD# rise time of
5
1
Guaranteed by design, not 100% tested in production.
2
See timing diagrams for timing requirements.
3
Input frequency should be measured at the REF output pin and tuned to ideal 14.31818MHz to meet
ppm frequency accuracy on PLL outputs.
Input Capacitance1
0756A—09/10/04
4
UNITS NOTES
ICS952621
Integrated
Circuit
Systems, Inc.
Electrical Characteristics - CPU & SRC 0.7V Current Mode Differential Pair
TA = 0 - 70°C; VDD = 3.3V +/-5%; CL =2pF
PARAMETER
SYMBOL
CONDITIONS
MIN
Current Source Output
Impedance
Zo
VO = Vx
3000
Voltage High
VHigh
Statistical measurement on single
ended signal using oscilloscope
math function.
Measurement on single ended
signal using absolute value.
660
1
Voltage Low
VLow
Max Voltage
Min Voltage
Crossing Voltage (abs)
Vovs
Vuds
Vcross(abs)
Crossing Voltage (var)
d-Vcross
Long Accuracy
ppm
Average period
Tperiod
Absolute min period
Tabsmin
Rise Time
Fall Time
Rise Time Variation
Fall Time Variation
tr
tf
d-tr
d-tf
Variation of crossing over all
edges
see Tperiod min-max values
200MHz nominal
200MHz spread
166.66MHz nominal
166.66MHz spread
133.33MHz nominal
133.33MHz spread
100.00MHz nominal
100.00MHz spread
200MHz nominal
166.66MHz nominal/spread
133.33MHz nominal/spread
100.00MHz nominal/spread
VOL = 0.175V, VOH = 0.525V
VOH = 0.525V VOL = 0.175V
TYP
749
MAX
UNITS
NOTES
Ω
1
850
1
mV
-150
3
150
1150
-300
250
756
-7
350
550
mV
1
1
1
12
140
mV
1
ppm
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ps
ps
ps
ps
1,2
2
2
2
2
2
2
2
2
1,2
1,2
1,2
1,2
1
1
1
1
-300
4.9985
4.9985
5.9982
5.9982
7.4978
7.4978
9.9970
9.9970
4.8735
5.8732
7.3728
9.8720
175
175
0
5.0000
300
5.0015
5.0266
6.0000 6.0018
6.0320
7.5000 7.5023
5.4000
10.0000 10.0030
10.0533
279
280
30
30
700
700
125
125
1
mV
Measurement from differential
45
50.9
55
%
wavefrom
VT = 50%
tsk3
8
100
ps
Skew
Measurement from differential
tjcyc-cyc
Jitter, Cycle to cycle
40
125
ps
wavefrom
1
Guaranteed by design, not 100% tested in production.
2
All Long Term Accuracy and Clock Period specifications are guaranteed with the assumption that Ref output is at
14.31818MHz
SRC clock outputs run at only 100MHz or 200MHz, specs for 133.33 and 166.66 do not apply to SRC clock pair.
Duty Cycle
dt3
0756A—09/10/04
5
1
1
1
ICS952621
Integrated
Circuit
Systems, Inc.
Electrical Characteristics - 3V66 Mode: 3V66 [3:0]
TA = 0 - 70°C; VDD = 3.3V +/-5%; CL = 10-30 pF (unless otherwise specified)
PARAMETER
SYMBOL
CONDITIONS
Long Accuracy
ppm
see Tperiod min-max values
66.66MHz output nominal
Tperiod
Clock period
66.66MHz output spread
IOH = -1 mA
VOH
Output High Voltage
VOL
IOL = 1 mA
Output Low Voltage
V OH = 1.0 V
IOH
Output High Current
VOH = 3.135 V
VOL = 1.95 V
IOL
Output Low Current
VOL = 0.4 V
Edge Rate
Rising edge rate
Edge Rate
Falling edge rate
VOL = 0.4 V, VOH = 2.4 V
tr1
Rise Time
tf1
VOH = 2.4 V, VOL = 0.4 V
Fall Time
dt1
VT = 1.5 V
Duty Cycle
Skew
tsk1
VT = 1.5 V
Jitter
tjcyc-cyc
VT = 1.5 V 3V66
MIN
-300
14.9955
14.9955
2.4
TYP
MAX
300
15.0045
15.0799
Notes
1,2
2
2
38
4
4
2
2
55
UNITS
ppm
ns
ns
V
V
mA
mA
mA
mA
V/ns
V/ns
ns
ns
%
250
ps
1
250
ps
1
0.55
-33
-33
30
1
1
0.5
0.5
45
1.78
1.72
49.9
80
172
1
1
1
1
1
1
Guaranteed by design, not 100% tested in production.
2
All Long Term Accuracy and Clock Period specifications are guaranteed with the assumption that Ref output is at
14.31818MHz
Electrical Characteristics - PCICLK
TA = 0 - 70°C; VDD = 3.3V +/-5%; CL = 10-30 pF (unless otherwise specified)
PARAMETER
SYMBOL
CONDITIONS
MIN
Long Accuracy
ppm
see Tperiod min-max values
-300
29.9910
33.33MHz output nominal
Tperiod
Clock period
29.9910
33.33MHz output spread
VOH
IOH = -1 mA
Output High Voltage
2.4
VOL
IOL = 1 mA
Output Low Voltage
V OH = 1.0 V
IOH
Output High Current
VOH = 3.135 V
-33
VOL = 1.95 V
30
IOL
Output Low Current
VOL = 0.4 V
Edge Rate
Edge Rate
Rise Time
Fall Time
Duty Cycle
Skew
Jitter
tr1
tf1
dt1
tsk1
tjcyc-cyc
Rising edge rate
Falling edge rate
VOL = 0.4 V, VOH = 2.4 V
VOH = 2.4 V, VOL = 0.4 V
VT = 1.5 V
VT = 1.5 V
VT = 1.5 V 3V66
1
1
1
0.5
0.5
45
TYP
MAX
300
30.0090
30.1598
0.55
-33
1.78
1.72
51.2
59
140
38
4
4
2
2
55
500
250
UNITS
ppm
ns
ns
V
V
mA
mA
mA
mA
V/ns
V/ns
ns
ns
%
ps
ps
Guaranteed by design, not 100% tested in production.
2
All Long Term Accuracy and Clock Period specifications are guaranteed with the assumption that Ref output is at
14.31818MHz
0756A—09/10/04
6
Notes
1,2
2
2
1
1
1
1
1
1
1
ICS952621
Integrated
Circuit
Systems, Inc.
Electrical Characteristics - VCH, USB
TA = 0 - 70°C; VDD = 3.3V +/-5%; CL = 10-20 pF (unless otherwise specified)
PARAMETER
SYMBOL
Long Accuracy
Clock period
Output High Voltage
Output Low Voltage
ppm
Tperiod
VOH
VOL
CONDITIONS
MIN
TYP
MAX
UNITS Notes
see Tperiod min-max values
-200
200
ppm
48.008MHz output nominal
20.8257
20.8340 ns
IOH = -1 mA
2.4
V
IOL = 1 mA
0.55
V
V OH = 1.0 V
-29
mA
IOH
Output High Current
VOH = 3.135 V
-23
mA
VOL = 1.95 V
29
mA
IOL
Output Low Current
VOL = 0.4 V
27
mA
Rising edge rate
1
2
V/ns
Edge Rate
Edge Rate
Falling edge rate
1
2
V/ns
tr1
VOL = 0.4 V, VOH = 2.4 V
Rise Time
1
1.45
2
ns
tf1
VOH = 2.4 V, VOL = 0.4 V
Fall Time
1
1.37
2
ns
V
=
1.5
V
d
45
52.5
55
%
Duty Cycle
t1
T
VT = 1.5 V
tsk1
1
ns
Skew
125us period jitter
0.628
6
ns
Long Term Jitter
(8kHz frequency modulation
amplitude)
1
Guaranteed by design, not 100% tested in production.
2
All Long Term Accuracy and Clock Period specifications are guaranteed with the assumption that Ref output is at
14.31818MHz
1,2
2
1
1
1
1
1
1
1
Electrical Characteristics - 48MHz DOT Clock
TA = 0 - 70°C; VDD = 3.3V +/-5%; CL = 5-10 pF (unless otherwise specified)
PARAMETER
Long Accuracy
Clock period
Output High Voltage
Output Low Voltage
SYMBOL
ppm
Tperiod
VOH
VOL
Output High Current
IOH
Output Low Current
IOL
Notes
1,2
2
27
4
4
UNITS
ppm
ns
V
V
mA
mA
mA
mA
V/ns
V/ns
1
ns
1
VOH = 2.4 V, VOL = 0.4 V
0.5
0.89
1
ns
VT = 1.5 V
45
52.3
55
%
VT = 1.5 V
1
ns
125us period jitter
0.636
2
ns
Long Term Jitter
(8kHz frequency modulation
amplitude)
1
Guaranteed by design, not 100% tested in production.
2
All Long Term Accuracy and Clock Period specifications are guaranteed with the assumption that Ref output is at
14.31818MHz
1
1
1
Edge Rate
Edge Rate
Rise Time
Fall Time
Duty Cycle
Skew
tr1
CONDITIONS
see Tperiod min-max values
48.008MHz output nominal
IOH = -1 mA
IOL = 1 mA
V OH = 1.0 V
VOH = 3.135 V
VOL = 1.95 V
VOL = 0.4 V
Rising edge rate
Falling edge rate
MIN
-200
20.8257
2.4
VOL = 0.4 V, VOH = 2.4 V
0.5
tf1
dt1
tsk1
0756A—09/10/04
7
TYP
MAX
200
20.8340
0.55
-29
-23
29
2
2
0.87
1
1
1
ICS952621
Integrated
Circuit
Systems, Inc.
Electrical Characteristics - REF-14.318MHz
TA = 0 - 70°C; VDD = 3.3V +/-5%; CL = 10-20 pF (unless otherwise specified)
PARAMETER
SYMBOL
CONDITIONS
Long Accuracy
ppm
see Tperiod min-max values
Tperiod
Clock period
14.318 MHz output nominal
1
IOH = -1 mA
Output High Voltage
VOH
1
IOL = 1 mA
Output Low Voltage
VOL
V OH = 1.0 V
IOH
Output High Current
VOH = 3.135 V
VOL = 1.95 V
IOL
Output Low Current
VOL = 0.4 V
1
V
=
0.4
V, VOH = 2.4 V
Rise Time
tr1
OL
1
VOH = 2.4 V, VOL = 0.4 V
Fall Time
tf1
1
VT = 1.5 V
Skew
tsk1
1
VT = 1.5 V
Duty Cycle
dt1
Jitter
1
1
MIN
TYP
MAX
-300
300
69.8270
69.8550
2.4
0.4
-33
-33
30
38
0.5
1.93
2
0.5
1.92
2
14
500
45
VT = 1.5 V
tjcyc-cyc
UNITS
ppm
ns
V
V
mA
mA
mA
mA
ns
ns
ps
55
%
1
400
1000
ps
1
Group to Group Skews at Common Transition Edges
SYMBOL
S3V66-PCI
SDOT_USB
SDOT_VCH
CONDITIONS
3V66 (4:0) leads 33MHz PCI
180 degrees out of phase
in phase
0756A—09/10/04
8
MIN
1.50
0.00
0.00
1
1
1
53.8
Guaranteed by design, not 100% tested in production.
GROUP
3V66 to PCI
DOT-USB
DOT-VCH
Notes
1
TYP
2.0
MAX
3.50
1.00
1.00
UNITS
ns
ns
ns
ICS952621
Integrated
Circuit
Systems, Inc.
2
I C Table: Read-Back Register
Pin #
Byte 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
-
Bit 0
-
Name
Control Function
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
Freq Select 1 Read
FSB
Back
Freq Select 0 Read
FSA
Back
Type
R
R
R
R
R
0
1
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
READBACK of
CPU(2:0) Frequency
PWD
X
X
X
X
X
X
X
X
2
I C Table: Spreading and Device Behavior Control Register
Name
Control Function
Pin #
Byte 1
SRC Free-Running
SRC/SRC#
Bit 7
Control
SRC
Output Control
Bit 6
RESERVED
Bit 5
RESERVED
Bit 4
RESERVED
Bit 3
RESERVED
Bit 2
CPUT1/CPUC1
Output Control
Bit 1
CPUT0/CPUC0
Output Enable
Bit 0
Type
RW
RW
R
R
R
R
RW
RW
0
1
FREE- STOPPAB
RUN
LE
Disable
Enable
RESERVED
RESERVED
RESERVED
RESERVED
Disable
Enable
Disable
Enable
PWD
0
1
X
X
X
X
1
1
2
I C Table: Output Control Register
Pin #
Byte 2
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
SRC_PD#
Drive Mode
SRC_Stop#
Drive Mode
RESERVED
CPUT1_PD# Drive Mode
CPUT0_PD# Drive Mode
RESERVED
RESERVED
RESERVED
Control Function
Type
0
1
PWD
0: Driven in PD#
RW
Driven
Hi-Z
0
RW
Driven
Hi-Z
0
RW
RW
-
RESERVED
Driven
Hi-Z
Driven
Hi-Z
RESERVED
RESERVED
RESERVED
X
0
0
X
X
X
0: Driven in
PCI_Stop#
RESERVED
0:driven in PD#
1: Tri-stated
RESERVED
RESERVED
RESERVED
2
I C Table: Output Control Register
Pin #
Byte 3
Name
Bit 7
PCI_Stop#
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
RESERVED
PCICLK5
PCICLK4
PCICLK3
PCICLK2
PCICLK1
PCICLK0
Control Function
PCI_Stop# Control
0:all stoppable PCI
are stopped
RESERVED
Output Control
Output Control
Output Control
Output Control
Output Control
Output Control
0756A—09/10/04
9
Type
0
1
PWD
RW
Enable
Disable
1
RW
RW
RW
RW
RW
RW
RESERVED
Disable
Enable
Disable
Enable
Disable
Enable
Disable
Enable
Disable
Enable
Disable
Enable
X
1
1
1
1
1
1
ICS952621
Integrated
Circuit
Systems, Inc.
2
I C Table: Output Control Register
Byte 4
Pin #
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
Control Function
Type
0
1
PWD
48MHz_USB
2x output drive
48MHz_USB
RESERVED
RESERVED
RESERVED
PCICLK_F2
PCICLK_F1
PCICLK_F0
0=2x drive
RW
2x drive
1xdrive
1
Output Control
RESERVED
RESERVED
RESERVED
Output Control
Output Control
Output Control
RW
RW
RW
RW
Disable
Enable
RESERVED
RESERVED
RESERVED
stoppable Free-run
stoppable Free-run
stoppable Free-run
1
X
X
X
1
1
1
Control Function
Output Control
Output Control
Type
RW
RW
0
Disable
Disable
1
Enable
Enable
PWD
1
1
Output Select
RW
3V66
VCH
0
2
I C Table: Output Control Register
Pin #
Byte 5
Name
DOT_48MHZ
Bit 7
CPU_T/C_ITP
Bit 6
3V66_3/VCH
Bit 5
Frequency Select
Bit 4
3V66_3/VCH
Frequency Select
Output Control
RW
Disable
Enable
1
Bit 3
Bit 2
Bit 1
Bit 0
RESERVED
3V66_2
3V66_1
3V66_0
RESERVED
Output Control
Output Control
Output Control
RW
RW
RW
RESERVED
Disable
Enable
Disable
Enable
Disable
Enable
X
1
1
1
Control Function
Test Clock Mode
FS_A and FS_B
Operation
SRC Frequency
Select
Down/Center
Spread Spectrum
Enable
Output Control
Output Control
Type
-
0
Disable
-
1
Enable
-
PWD
0
0
-
Normal
Test Mode
0
-
100MHz
200MHz
0
-
Center
Spread
ON
Enable
Enable
0
RW
RW
Down
Spread
OFF
Disable
Disable
1
1
Control Function
Type
R
R
R
R
R
R
R
R
0
-
1
-
PWD
0
0
0
0
0
0
0
1
2
I C Table: Output Control and Fix Frequecy Register
Pin #
Name
Byte 6
Test Clock Mode
Bit 7
RESERVED
Bit 6
Bit 5
CPU *2 Test Clock
Bit 4
SRC Frequency Select
Bit 3
Spread Spectrum Type
Bit 2
Spread Spectrum Mode
Bit 1
Bit 0
REF1
REF0
0
2
I C Table: Vendor & Revision ID Register
Name
Pin #
Byte 7
RID3
Bit 7
RID2
Bit 6
RID1
Bit 5
RID0
Bit 4
VID3
Bit 3
VID2
Bit 2
VID1
Bit 1
VID0
Bit 0
REVISION ID
VENDOR ID
0756A—09/10/04
10
ICS952621
Integrated
Circuit
Systems, Inc.
2
I C Table: Byte Count Register
Byte 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Pin #
-
Name
BC7
BC6
BC5
BC4
BC3
BC2
BC1
BC0
Control Function
Type
0
1
PWD
Writing to this register
will configure how
many bytes will be
read back, default is
08 = 8 bytes.
RW
RW
RW
RW
RW
RW
RW
RW
-
-
0
0
0
0
1
0
0
0
0756A—09/10/04
11
ICS952621
Integrated
Circuit
Systems, Inc.
PD#, Power Down
PD# is an asynchronous active low input used to shut off all clocks cleanly prior to clock power.
When PD# is asserted low all clocks will be driven low before turning off the VCO. In PD# de-assertion all clocks will start
without glitches.
PWRDWN#
CPU
CPU #
SRC
SRC#
3V66
PCIF/PCI
USB/DOT
REF
1
Normal
Normal
Normal
Normal
66MHz
33MHz
48MHz
14.318MHz
0
Iref * 2 or
Float
Float
Iref * 2
or Float
Float
Low
Low
Low
Low
Note
Notes:
1. Refer to tristate control of CPU and SRC clocks in section 7.7 for tristate timing and operation.
2. Refer to Control Registers in section 16 for CPU_Stop, SRC_Stop and PwrDwn SMBus tristate control addresses.
PD# Assertion
PD# should be sampled low by 2 consecutive CPU# rising edges before stopping clocks. All single ended clocks will be
held low on their next high to low transition.
All differential clocks will be held high on the next high to low transition of the complimentary clock. If the control register
determining to drive mode is set to 'tri-state', the differential pair will be stopped in tri-state mode, undriven.
When the drive mode but corresponding to the CPU or SRC clock of interest is set to '0' the true clock will be driven high at
2 x Iref and the complementary clock will be tristated. If the control register is programmed to '1' both clocks will the
tristated.
PWRDWN#
CPU, 133MHz
CPU#, 133MHz
SRC, 100MHz
SRC#, 100MHz
3V66, 66MHz
USB, 48MHz
PCI, 33MHz
REF, 14.31818
0756A—09/10/04
12
ICS952621
Integrated
Circuit
Systems, Inc.
PD# De-assertion
The time from the de-assertion of PD# or until power supply ramps to get stable clocks will be less than 1.8ms. If the drive
mode control bit for PD# tristate is programmed to '1' the stopped differential pair must first be driven high to a minimum of
200mV in less than 300µs of PD# deassertion.
Tstable
<1.8mS
PWRDWN#
CPU, 133MHz
CPU#, 133MHz
SRC, 100MHz
SRC# 100MHz
3V66, 66MHz
USB, 48MHz
PCI, 33MHz
REF, 14.31818
Tdrive_PwrDwn#
<300µS, >200mV
3V66_3/VCH Pin Functionality
The 3V66_4/VCH pin can be configured to be a 66.66MHz modulated output or a non-spread 48MHz output. The default is
3V66 clock. The switching is controlled by Byte 5 Bit 5. If it is set to '1' this pin will output the 48MHz VCH clock. The output
will go low on the falling edge of 3V66 for a minimum of 7.49ns. Then the output will transition to 48MHz on the next rising
edge of DOT_48 clock.
3V66
3V66_4/VCH
DOT_48
7.49nS min
0756A—09/10/04
13
ICS952621
Integrated
Circuit
Systems, Inc.
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) 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
0756A—09/10/04
14
ICS952621
Integrated
Circuit
Systems, Inc.
c
N
SYMBOL
L
E1
A
A1
b
c
D
E
E1
e
h
L
N
α
E
INDEX
AREA
1 2
α
h x 45°
D
A
In Millimeters
COMMON DIMENSIONS
MIN
MAX
2.41
2.80
0.20
0.40
0.20
0.34
0.13
0.25
SEE VARIATIONS
10.03
10.68
7.40
7.60
0.635 BASIC
0.38
0.64
0.50
1.02
SEE VARIATIONS
0°
8°
In Inches
COMMON DIMENSIONS
MIN
MAX
.095
.110
.008
.016
.008
.0135
.005
.010
SEE VARIATIONS
.395
.420
.291
.299
0.025 BASIC
.015
.025
.020
.040
SEE VARIATIONS
0°
8°
A1
-Ce
VARIATIONS
N
SEATING
PLANE
b
48
.10 (.004) C
D mm.
MIN
15.75
D (inch)
MAX
16.00
MIN
.620
Reference Doc.: JEDEC Publication 95, MO-118
10-0034
Ordering Information
ICS952621yFLF-T
Example:
ICS XXXX y F LF- T
Designation for tape and reel packaging
Lead Free (Optional)
Package Type
F = SSOP
Revision Designator (will not correlate with datasheet revision)
Device Type
Prefix
ICS = Standard Device
0756A—09/10/04
15
MAX
.630