CYPRESS W48C101-01

PRELIMINARY
W48C101-01
Spread Spectrum BX System Frequency Generator
Features
CPU0:3 Clock Skew: ...................................................175 ps
• Maximized EMI suppression using Cypress’s Spread
Spectrum technology
• Four copies of CPU output
• Eight copies of PCI output (Synchronous w/CPU
output)
• Two copies of 14.318-MHz IOAPIC output
• Two copies of 48-MHz USB output
• Three buffered copies of 14.318-MHz reference input
• Input is a 14.318-MHz XTAL or reference signal
• Selectable 100-MHz or 66-MHz CPU outputs
• Power management control input pins
• Test mode and output three-state capability
PCI_F, PCI1:7 Clock Skew: ......................................... 500 ps
CPU to PCI Clock Skew: .............. 1.5 to 4.0 ns (CPU Leads)
Logic inputs have 250-kΩ pull-up resistors except SEL100/66#.
Table 1. Pin Selectable Frequency
SEL
100/66#
SEL1
SEL0
0
0
0
0
0
1
0
1
0
CPU
PCI
(MHz) (MHz)
HI-Z
SPREAD#=0
HI-Z
Don’t Care
66.6
33.3
±0.9% Center
66.6
33.3
–1% Down
0
1
1
66.6
33.3
–0.5% Down
1
0
0
X1/2
X1/6
Don’t Care
Key Specifications
1
0
1
100
33.3
±0.9% Center
Supply Voltages: ....................................... VDDQ3 = 3.3V±5%
VDDQ2 = 2.5V±5%
1
1
0
100
33.3
–1% Down
1
1
1
100
33.3
–0.5% Down
CPU0:3 Jitter (Cycle to Cycle): ................................... 200 ps
Block Diagram
Pin Configuration
VDDQ3
REF0
X1
X2
REF1
XTAL
OSC
REF2
PLL Ref Freq
VDDQ2
APIC0
APIC1
VDDQ2
CPU_STOP#
CPU0
CPU1
Stop
Clock
Control
SEL100/66#
SEL0
SEL1
CPU2
PLL 1
CPU3
÷2/÷3
REF0
REF1
GND
X1
X2
GND
PCI_F
PCI1
VDDQ3
PCI2
PCI3
GND
PCI4
PCI5
VDDQ3
PCI6
PCI7
GND
VDDQ3
GND
VDDQ3
48MHz
48MHz
GND
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
VDDQ3
REF2
VDDQ2
APIC0
APIC1
GND
NC
VDDQ2
CPU0
CPU1
GND
VDDQ2
CPU2
CPU3
GND
VDDQ3
GND
PCI_STOP#
CPU_STOP#
PWR_DWN#
SPREAD#
SEL0
SEL1
SEL100/66#
VDDQ3
SPREAD#
PCI_F
PCI1
Stop
Clock
Control
PCI2
PCI3
PCI_STOP#
PCI4
PCI5
PCI6
Power
Down
Control
PWR_DWN#
PCI7
VDDQ3
48MHz
PLL2
48MHz
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
•
CA 95134 •
408-943-2600
October 7, 1999, rev. **
PRELIMINARY
W48C101-01
Pin Definitions
Pin
No.
Pin
Type
CPU0:3
40, 39, 36,
35
O
CPU Clock Outputs 0 through 3: These four CPU clock outputs are controlled by
the CPU_STOP# control pin. Output voltage swing is controlled by voltage applied
to VDDQ2.
PCI1:7
8, 10, 11, 13,
14, 16, 17
O
PCI Bus Clock Outputs 1 through 7: These seven PCI clock outputs are controlled
by the PCI_STOP# control pin. Output voltage swing is controlled by voltage applied
to VDDQ3.
PCI_F
7
O
Fixed PCI Clock Output: Unlike PCI1:7 outputs, this output is not controlled by the
PCI_STOP# control pin. Output voltage swing is controlled by voltage applied to
VDDQ3.
CPU_STOP#
30
I
CPU_STOP# Input: When brought LOW, clock outputs CPU0:3 are stopped LOW
after completing a full clock cycle (2–3 CPU clock latency). When brought HIGH,
clock outputs CPU0:3 start beginning with a full clock cycle (2–3 CPU clock latency).
PCI_STOP#
31
I
PCI_STOP# Input: The PCI_STOP# input enables the PCI 1:7 outputs when HIGH
and causes them to remain at logic 0 when LOW. The PCI_STOP signal is latched
on the rising edge of PCI_F. Its effects take place on the next PCI_F clock cycle.
SPREAD#
28
I
SPREAD# Input: When brought LOW this pin activates Spread Spectrum clocking.
APIC0:1
45, 44
O
I/O APIC Clock Outputs: Provides 14.318-MHz fixed frequency. The output voltage swing is controlled by VDDQ2.
48MHz
22, 23
O
48-MHz Outputs: Fixed clock outputs at 48 MHz. Output voltage swing is controlled
by voltage applied to VDDQ3.
REF0:2
1, 2, 47
O
Fixed 14.318-MHz Outputs 0 through 2: Used for various system applications.
Output voltage swing is controlled by voltage applied to VDDQ3.
25, 26, 27
I
Frequency Selection Input: Selects power-up default CPU clock frequency as
shown in Table 1 on page 1.
X1
4
I
Crystal Connection or External Reference Frequency Input: Connect to either
a 14.318-MHz crystal or reference signal.
X2
5
I
Crystal Connection: An input connection for an external 14.318-MHz crystal. If
using an external reference, this pin must be left unconnected.
PWR_DWN#
29
I
Power Down Control: When this input is LOW, device goes into a low-power condition. All outputs are held LOW while in power-down. CPU and PCI clock outputs
are stopped LOW after completing a full clock cycle (2–3 CPU clock cycle latency).
When brought HIGH, CPU, SDRAM and PCI outputs start with a full clock cycle at
full operating frequency (3 ms maximum latency).
VDDQ3
9, 15, 19, 21,
33, 48
P
Power Connection: Connect to 3.3V supply.
VDDQ2
37,41,46
P
Power Connection: Power supply for CPU0:3 and APIC0:1 output buffers. Connect
to 2.5V supply.
3, 6, 12, 18,
20, 24, 32,
34, 38, 43
G
Ground Connection: Connect all ground pins to the common system ground
plane.
42
-
No Connect: Do not connect.
Pin Name
SEL100/66#
SEL1:0
GND
NC
Pin Description
2
PRELIMINARY
W48C101-01
Spread Spectrum Clocking
Where P is the percentage of deviation and F is the frequency
in MHz where the reduction is measured.
The device generates a clock that is frequency modulated in
order to increase the bandwidth that it occupies. By increasing
the bandwidth of the fundamental and its harmonics, the amplitudes of the radiated electromagnetic emissions are reduced. This effect is depicted in Figure 1.
The output clock is modulated with a waveform depicted in
Figure 2. This waveform, as discussed in “Spread Spectrum
Clock Generation for the Reduction of Radiated Emissions” by
Bush, Fessler, and Hardin produces the maximum reduction
in the amplitude of radiated electromagnetic emissions. The
deviation selected for this chip is –0.5%, –1.0%, or ±0.9% of
the selected frequency. Figure 2 details the Cypress spreading
pattern. Cypress does offer options with more spread and
greater EMI reduction. Contact your local Sales representative
for details on these devices.
As shown in Figure 1, a harmonic of a modulated clock has a
much lower amplitude than that of an unmodulated signal. The
reduction in amplitude is dependent on the harmonic number
and the frequency deviation or spread. The equation for the
reduction is:
Spread Spectrum clocking is activated or deactivated by selecting the appropriate values for SPREAD#.
dB = 6.5 + 9*log10(P) + 9*log10(F)
Highest peak
∆
non-SSC
SSC
δ of fnom
fnom
Figure 1. Clock Harmonic with and without SSCG Modulation Frequency Domain Representation
MIN (–0.5%)
Figure 2. Typical Modulation Profile
3
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
FREQUENCY
MAX (+0.5%)
PRELIMINARY
W48C101-01
Absolute Maximum Ratings
above those specified in the operating sections of this specification is not implied. Maximum conditions for extended periods may affect reliability.
Stresses greater than those listed in this table may cause permanent damage to the device. These represent a stress rating
only. Operation of the device at these or any other conditions
Parameter
Description
Rating
Unit
V
VDD, VIN
Voltage on any pin with respect to GND
–0.5 to +7.0
–65 to +150
°C
0 to +70
°C
–55 to +125
°C
2 (min.)
kV
TSTG
Storage Temperature
TA
Operating Temperature
TB
Ambient Temperature under Bias
ESDPROT
Input ESD Protection
DC Electrical Characteristics: TA = 0°C to +70°C, VDDQ3 = 3.3V±5%, VDDQ2 = 2.5V±5%
Parameter
Description
Test Condition
Min.
Typ.
Max.
Unit
Supply Current
IDDQ3
3.3V Supply Current
CPU0:3 = 100 MHz
Outputs Loaded[1]
120
mA
IDDQ2
2.5V Supply Current
CPU0:3 = 100 MHz
Outputs Loaded[1]
65
mA
GND – 0.3
0.8
V
2.0
VDD + 0.3
V
Logic Inputs
VIL
Input Low Voltage
VIH
Input High Voltage
[2]
IIL
Input Low Current
–25
µA
IIH
Input High Current[2]
10
µA
IIL
Input Low Current (SEL100/66#)
–5
µA
IIH
Input High Current (SEL100/66#)
5
µA
50
mV
Clock Outputs
VOL
Output Low Voltage
IOL = 1 mA
VOH
Output High Voltage
IOH = –1 mA
3.1
VOH
Output High Voltage
CPU0:3, APIC0:1
IOH = –1 mA
2.2
IOL
Output Low Current
CPU0:3
VOL = 1.25V
45
65
100
mA
PCI_F, PCI1:7
VOL = 1.5V
70
100
145
mA
APIC0:1
VOL = 1.25V
60
90
140
mA
REF0:2
VOL = 1.5V
45
65
100
mA
48MHz
VOL = 1.5V
45
65
100
mA
CPU0:3
VOL = 1.25V
45
65
100
mA
IOH
Output High Current
V
V
PCI_F, PCI1:7
VOL = 1.5V
65
95
135
mA
APIC0:1
VOL = 1.25V
55
80
115
mA
REF0:2
VOL = 1.5V
45
65
100
mA
48MHz
VOL = 1.5V
45
65
100
mA
Notes:
1. All clock outputs loaded with 6" 60Ω transmission lines with 20-pF capacitors.
2. W48C101-01 logic inputs have internal pull-up devices, except SEL100/66# (pull-ups not full CMOS level).
4
PRELIMINARY
W48C101-01
DC Electrical Characteristics: TA = 0°C to +70°C, VDDQ3 = 3.3V±5%, VDDQ2 = 2.5V±5% (continued)
Parameter
Description
Test Condition
Min.
Typ.
Max.
Unit
Crystal Oscillator
VTH
X1 Input Threshold Voltage[3]
CLOAD
Load Capacitance, as seen by External Crystal
CIN,X1
[5]
X1 Input Capacitance
[4]
Pin X2 unconnected
1.65
V
14
pF
28
pF
Pin Capacitance/Inductance
CIN
Input Pin Capacitance
COUT
Output Pin Capacitance
6
pF
LIN
Input Pin Inductance
7
nH
Except X1 and X2
5
pF
Notes:
3. X1 input threshold voltage (typical) is VDD/2.
4. The W48C101-01 contains an internal crystal load capacitor between pin X1 and ground and another between pin X2 and ground. Total load placed on crystal
is 14 pF; this includes typical stray capacitance of short PCB traces to crystal.
5. X1 input capacitance is applicable when driving X1 with an external clock source (X2 is left unconnected).
AC Electrical Characteristics
TA = 0°C to +70°C, VDDQ3 = 3.3V±5%,VDDQ2 = 2.5V± 5%, fXTL = 14.31818 MHz
AC clock parameters are tested and guaranteed over stated operating conditions using the stated lump capacitive load at the
clock output; Spread Spectrum clocking is disabled.
CPU Clock Outputs, CPU0:3 (Lump Capacitance Test Load = 20 pF)
CPU = 66.6 MHz
Parameter
Description
Test Condition/Comments
CPU = 100 MHz
Min. Typ. Max. Min.
Typ. Max. Unit
tP
Period
Measured on rising edge at 1.25V
15
tH
High Time
Duration of clock cycle above 2.0V
5.2
3.0
ns
tL
Low Time
Duration of clock cycle below 0.4V
5.0
2.8
ns
tR
Output Rise Edge Rate Measured from 0.4V to 2.0V
1
4
1
4
V/ns
tF
Output Fall Edge Rate
Measured from 2.0V to 0.4V
1
4
1
4
V/ns
tD
Duty Cycle
Measured on rising and falling edge at
1.25V
45
55
45
55
%
tJC
Jitter, Cycle-to-Cycle
Measured on rising edge at 1.25V. Maximum difference of cycle time between
two adjacent cycles.
200
200
ps
175
175
ps
3
3
ms
tSK
Output Skew
Measured on rising edge at 1.25V
fST
Frequency Stabilization from Power-up
(cold start)
Assumes full supply voltage reached
within 1 ms from power-up. Short cycles
exist prior to frequency stabilization.
Zo
AC Output Impedance
Average value during switching transition. Used for determining series termination value.
5
15.5
20
10
10.5
20
ns
Ω
PRELIMINARY
W48C101-01
PCI Clock Outputs, PCI1:7 and PCI_F (Lump Capacitance Test Load = 30 pF
CPU = 66.6/100 MHz
Parameter
Description
Test Condition/Comments
Min.
Typ.
Max.
Unit
tP
Period
Measured on rising edge at 1.5V
30
ns
tH
High Time
Duration of clock cycle above 2.4V
12
ns
tL
Low Time
Duration of clock cycle below 0.4V
12
ns
tR
Output Rise Edge Rate
Measured from 0.4V to 2.4V
1
4
V/ns
tF
Output Fall Edge Rate
Measured from 2.4V to 0.4V
1
4
V/ns
tD
Duty Cycle
Measured on rising and falling edge at 1.5V
45
55
%
tJC
Jitter, Cycle-to-Cycle
Measured on rising edge at 1.5V. Maximum
difference of cycle time between two adjacent cycles.
250
ps
tSK
Output Skew
Measured on rising edge at 1.5V
500
ps
tO
CPU to PCI Clock Skew
Covers all CPU/PCI outputs. Measured on rising
edge at 1.5V. CPU leads PCI output.
4
ns
fST
Frequency Stabilization
from Power-up (cold
start)
Assumes full supply voltage reached within 1 ms
from power-up. Short cycles exist prior to frequency
stabilization.
3
ms
Zo
AC Output Impedance
Average value during switching transition. Used for
determining series termination value.
1.5
Ω
15
APIC0:1 Clock Outputs (Lump Capacitance Test Load = 20 pF)
CPU = 66.6/100MHz
Parameter
Description
f
Frequency, Actual
Test Condition/Comments
Min.
Frequency generated by crystal oscillator
Typ.
Max.
14.31818
Unit
MHz
tR
Output Rise Edge Rate
Measured from 0.4V to 2.0V
1
4
V/ns
tF
Output Fall Edge Rate
Measured from 2.0V to 0.4V
1
4
V/ns
tD
Duty Cycle
Measured on rising and falling edge at 1.25V
45
fST
Frequency Stabilization
from Power-up (cold start)
Assumes full supply voltage reached within
1 ms from power-up. Short cycles exist prior to
frequency stabilization.
Zo
AC Output Impedance
Average value during switching transition.
Used for determining series termination value.
55
%
1.5
ms
Ω
15
REF0:2 Clock Outputs (Lump Capacitance Test Load = 20 pF)
CPU = 66.6/100 MHz
Parameter
Description
Test Condition/Comments
f
Frequency, Actual
Frequency generated by crystal oscillator
Min.
Typ.
Max.
14.318
Unit
MHz
tR
Output Rise Edge Rate
Measured from 0.4V to 2.4V
0.5
2
V/ns
tF
Output Fall Edge Rate
Measured from 2.4V to 0.4V
0.5
2
V/ns
tD
Duty Cycle
Measured on rising and falling edge at 1.5V
45
55
%
fST
Frequency Stabilization from
Power-up (cold start)
Assumes full supply voltage reached within 1 ms
from power-up. Short cycles exist prior to
frequency stabilization.
3
ms
Zo
AC Output Impedance
Average value during switching transition. Used for
determining series termination value.
6
25
Ω
PRELIMINARY
W48C101-01
48-MHz Clock Outputs (Lump Capacitance Test Load = 20 pF = 66.6/100 MHz)
CPU = 66.6/100 MHz
Parameter
f
Description
Frequency, Actual
Test Condition/Comments
Min.
Determined by PLL divider ratio (see m/n below)
Typ.
Max.
Unit
48.008
MHz
ppm
fD
Deviation from 48 MHz
(48.008 – 48)/48
+167
m/n
PLL Ratio
(14.31818 MHz x 57/17 = 48.008 MHz)
57/17
tR
Output Rise Edge Rate
Measured from 0.4V to 2.4V
1
4
V/ns
tF
Output Fall Edge Rate
Measured from 2.4V to 0.4V
1
4
V/ns
tD
Duty Cycle
Measured on rising and falling edge at 1.5V
45
55
%
fST
Frequency Stabilization
from Power-up (cold start)
Assumes full supply voltage reached within 1 ms
from power-up. Short cycles exist prior to frequency stabilization.
3
ms
Zo
AC Output Impedance
Average value during switching transition. Used
for determining series termination value.
Ordering Information
Ordering Code
W48C101
Freq. Mask
Code
Package
Name
-01
H
Package Type
48-pin SSOP (300 mils)
Document #: 38-00852
7
25
Ω
PRELIMINARY
W48C101-01
Package Diagram
48-Pin Small Shrink Outline Package (SSOP, 300 mils)
Summary of nominal dimensions in inches:
Body Width: 0.296
Lead Pitch: 0.025
Body Length: 0.625
Body Height: 0.102
© Cypress Semiconductor Corporation, 1999. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use
of any circuitry other than circuitry embodied in a Cypress Semiconductor product. Nor does it convey or imply any license under patent or other rights. Cypress Semiconductor does not authorize
its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress
Semiconductor products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress Semiconductor against all charges.