W48C101-01
Spread Spectrum BX System Frequency Generator
Features
• 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 CPU0:3 Jitter (Cycle to Cycle): ................................... 200 ps CPU0:3 Clock Skew: .................................................. 175 ps 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-k pull-up resistors except SEL100/66#. Table 1. Pin Selectable Frequency SEL 100/66# 0 0 0 0 1 1 1 1 SEL1 0 0 1 1 0 0 1 1 SEL0 0 1 0 1 0 1 0 1 CPU PCI (MHz) (MHz) HI-Z 66.6 66.6 66.6 X1/2 100 100 100 HI-Z 33.3 33.3 33.3 X1/6 33.3 33.3 33.3 SPREAD#=0 Don’t Care ±0.9% Center –1% Down –0.5% Down Don’t Care ±0.9% Center –1% Down –0.5% Down
Key Specifications
Supply Voltages:........................................VDDQ3 = 3.3V±5% ............................................................................................... VDDQ2 = 2.5V±5% or 3.3V±5%
Rev 1.0, November 28, 2006
2200 Laurelwood Road, Santa Clara, CA 95054 Tel:(408) 855-0555 Fax:(408) 855-0550
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www.SpectraLinear.com
W48C101-01
Block Diagram
VDDQ3 REF0 X1 X2 XTAL OSC PLL Ref Freq VDDQ2 APIC0 APIC1 VDDQ2 CPU_STOP# Stop Clock Control SEL100/66# SEL0 SEL1 SPREAD# PLL 1 ÷2/÷3 VDDQ3 PCI_F Stop Clock Control PCI_STOP# PCI1 PCI2 PCI3 CPU0 CPU1 REF1 REF2
Pin Configuration
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 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 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#
CPU2 CPU3
PCI4 PCI5 PWR_DWN# Power Down Control PCI6 PCI7
VDDQ3 PLL2 48MHz 48MHz
Rev 1.0, November 28, 2006
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W48C101-01
Pin Definitions
Pin Name CPU0:3 Pin No. 40, 39, 36, 35 8, 10, 11, 13, 14, 16, 17 7 Pin Type O Pin Description 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. 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. 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# 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# 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# Input: When brought LOW this pin activates Spread Spectrum clocking. I/O APIC Clock Outputs: Provides 14.318-MHz fixed frequency. The output voltage swing is controlled by VDDQ2. 48-MHz Outputs: Fixed clock outputs at 48 MHz. Output voltage swing is controlled by voltage applied to VDDQ3. Fixed 14.318-MHz Outputs 0 through 2: Used for various system applications. Output voltage swing is controlled by voltage applied to VDDQ3. Frequency Selection Input: Selects power-up default CPU clock frequency as shown in Table 1 on page 1. Crystal Connection or External Reference Frequency Input: Connect to either a 14.318-MHz crystal or reference signal. Crystal Connection: An input connection for an external 14.318-MHz crystal. If using an external reference, this pin must be left unconnected. 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). Power Connection: Connect to 3.3V supply. Power Connection: Power supply for CPU0:3 and APIC0:1 output buffers. Connect to 2.5V supply or 3.3V supply. Ground Connection: Connect all ground pins to the common system ground plane. No Connect: Do not connect.
PCI1:7
O
PCI_F
O
CPU_STOP#
30
I
PCI_STOP#
31
I
SPREAD# APIC0:1 48MHz REF0:2 SEL100/66# SEL1:0 X1 X2 PWR_DWN#
28 45, 44 22, 23 1, 2, 47 25, 26, 27 4 5 29
I O O O I I I I
VDDQ3 VDDQ2 GND
9, 15, 19, 21, 33, 48 37,41,46 3, 6, 12, 18, 20, 24, 32, 34, 38, 43 42
P P G
NC
-
Rev 1.0, November 28, 2006
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W48C101-01
Spread Spectrum Clocking
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. 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: dB = 6.5 + 9*log10(P) + 9*log10(F) Where P is the percentage of deviation and F is the frequency in MHz where the reduction is measured. 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. Spread Spectrum clocking is activated or deactivated by selecting the appropriate values for SPREAD#.
Highest k
nonSSC
S SC
o f f nom f nom
Figure 1. Clock Harmonic with and without SSCG Modulation Frequency Domain Representation
MAX (+0.5%)
FREQUENCY
10%
20%
30%
40%
50%
60%
70%
80%
90%
10%
20%
30%
40%
50%
60%
70%
80%
100%
90%
MIN (–0.5%)
Figure 2. Typical Modulation Profile
Rev 1.0, November 28, 2006
100%
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W48C101-01
Absolute Maximum Ratings[1]
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 condiParameter VDD, VIN TSTG TA TB ESDPROT Description Voltage on any pin with respect to GND Storage Temperature Operating Temperature Ambient Temperature under Bias Input ESD Protection tions above those specified in the operating sections of this specification is not implied. Maximum conditions for extended periods may affect reliability. Rating –0.5 to +7.0 –65 to +150 0 to +70 –55 to +125 2 (min.) Unit V °C °C °C kV
DC Electrical Characteristics: TA = 0°C to +70°C, VDDQ3 = 3.3V±5%, VDDQ2 = 2.5V±5%
Parameter Supply Current IDDQ3 IDDQ2 3.3V Supply Current 2.5V Supply Current CPU0:3 = 100 MHz Outputs Loaded[2] CPU0:3 = 100 MHz Outputs Loaded[2] GND – 0.3 2.0 120 65 mA mA Description Test Condition Min. Typ. Max. Unit
Logic Inputs VIL VIH IIL IIH IIL IIH VOL VOH VOH IOL Input Low Voltage Input High Voltage Input Low Current[3] Input High Current[3] Input Low Current (SEL100/66#) Input High Current (SEL100/66#) Output Low Voltage Output High Voltage Output High Voltage Output Low Current CPU0:3, APIC0:1 CPU0:3 PCI_F, PCI1:7 APIC0:1 REF0:2 48MHz IOH Output High Current CPU0:3 PCI_F, PCI1:7 APIC0:1 REF0:2 48MHz IOL = 1 mA IOH = –1 mA IOH = –1 mA VOL = 1.25V VOL = 1.5V VOL = 1.25V VOL = 1.5V VOL = 1.5V VOL = 1.25V VOL = 1.5V VOL = 1.25V VOL = 1.5V VOL = 1.5V 3.1 2.2 45 70 60 45 45 45 65 55 45 45 65 100 90 65 65 65 95 80 65 65 100 145 140 100 100 100 135 115 100 100 0.8 VDD + 0.3 –25 10 –5 5 50 V V µA µA µA µA mV V V mA mA mA mA mA mA mA mA mA mA
Clock Outputs
Notes: 1. Multiple Supplies: The voltage on any input or I/O pin cannot exceed the power pin during power-up. Power supply sequencing is NOT required. 2. All clock outputs loaded with 6" 60 transmission lines with 20-pF capacitors. 3. W48C101-01 logic inputs have internal pull-up devices, except SEL100/66# (pull-ups not full CMOS level).
Rev 1.0, November 28, 2006
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W48C101-01
DC Electrical Characteristics: TA = 0°C to +70°C, VDDQ3 = 3.3V±5%, VDDQ2 = 2.5V±5% (continued)
Parameter Crystal Oscillator VTH CLOAD CIN,X1 CIN COUT LIN X1 Input Threshold Voltage[4] Load Capacitance, as seen by External Crystal X1 Input Capacitance[6] Input Pin Capacitance Output Pin Capacitance Input Pin Inductance
[5]
Description
Test Condition
Min.
Typ. 1.65 14
Max.
Unit V pF pF
Pin X2 unconnected Except X1 and X2
28 5 6 7
Pin Capacitance/Inductance pF pF nH
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 tP tH tL tR tF tD tJC Description Period High Time Low Time Output Fall Edge Rate Duty Cycle Jitter, Cycle-to-Cycle Test Condition/Comments Measured on rising edge at 1.25V Duration of clock cycle above 2.0V Duration of clock cycle below 0.4V Measured from 2.0V to 0.4V Measured on rising and falling edge at 1.25V Measured on rising edge at 1.25V. Maximum difference of cycle time between two adjacent cycles. Measured on rising edge at 1.25V Assumes full supply voltage reached within 1 ms from power-up. Short cycles exist prior to frequency stabilization. Average value during switching transition. Used for determining series termination value. 20 15 5.2 5.0 1 1 45 4 4 55 200 15.5 CPU = 100 MHz Typ. Max. Unit 10.5 ns ns ns 4 4 55 200 V/ns V/ns % ps 10 3.0 2.8 1 1 45 Min. Typ. Max. Min.
Output Rise Edge Rate Measured from 0.4V to 2.0V
tSK fST
Output Skew Frequency Stabilization from Power-up (cold start) AC Output Impedance
175 3
175 3
ps ms
Zo
20
Notes: 4. X1 input threshold voltage (typical) is VDD/2. 5. 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. 6. X1 input capacitance is applicable when driving X1 with an external clock source (X2 is left unconnected).
Rev 1.0, November 28, 2006
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W48C101-01
PCI Clock Outputs, PCI1:7 and PCI_F (Lump Capacitance Test Load = 30 pF CPU = 66.6/100 MHz Parameter tP tH tL tR tF tD tJC tSK tO fST Description Period High Time Low Time Output Rise Edge Rate Output Fall Edge Rate Duty Cycle Jitter, Cycle-to-Cycle Output Skew CPU to PCI Clock Skew Frequency Stabilization from Power-up (cold start) AC Output Impedance Test Condition/Comments Measured on rising edge at 1.5V Duration of clock cycle above 2.4V Duration of clock cycle below 0.4V Measured from 0.4V to 2.4V Measured from 2.4V to 0.4V Measured on rising and falling edge at 1.5V Measured on rising edge at 1.5V. Maximum difference of cycle time between two adjacent cycles. Measured on rising edge at 1.5V Covers all CPU/PCI outputs. Measured on rising edge at 1.5V. CPU leads PCI output. Assumes full supply voltage reached within 1 ms from power-up. Short cycles exist prior to frequency stabilization. Average value during switching transition. Used for determining series termination value. 15 1.5 Min. 30 12 12 1 1 45 4 4 55 250 500 4 3 Typ. Max. Unit ns ns ns V/ns V/ns % ps ps ns ms
Zo
APIC0:1 Clock Outputs (Lump Capacitance Test Load = 20 pF) CPU = 66.6/100MHz Parameter f tR tF tD fST Description Frequency, Actual Output Rise Edge Rate Output Fall Edge Rate Duty Cycle Frequency Stabilization from Power-up (cold start) AC Output Impedance Test Condition/Comments Frequency generated by crystal oscillator Measured from 0.4V to 2.0V Measured from 2.0V to 0.4V Measured on rising and falling edge at 1.25V Assumes full supply voltage reached within 1 ms from power-up. Short cycles exist prior to frequency stabilization. Average value during switching transition. Used for determining series termination value. 15 1 1 45 Min. Typ. 14.31818 4 4 55 1.5 Max. Unit MHz V/ns V/ns % ms
Zo
REF0:2 Clock Outputs (Lump Capacitance Test Load = 20 pF) CPU = 66.6/100 MHz Parameter f tR tF tD fST Description Frequency, Actual Output Rise Edge Rate Output Fall Edge Rate Duty Cycle Frequency Stabilization from Power-up (cold start) AC Output Impedance Test Condition/Comments Frequency generated by crystal oscillator Measured from 0.4V to 2.4V Measured from 2.4V to 0.4V Measured on rising and falling edge at 1.5V Assumes full supply voltage reached within 1 ms from power-up. Short cycles exist prior to frequency stabilization. Average value during switching transition. Used for determining series termination value. 25 0.5 0.5 45 Min. Typ. 14.318 2 2 55 3 Max. Unit MHz V/ns V/ns % ms
Zo
Rev 1.0, November 28, 2006
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W48C101-01
48-MHz Clock Outputs (Lump Capacitance Test Load = 20 pF = 66.6/100 MHz) CPU = 66.6/100 MHz Parameter f fD m/n tR tF tD fST Description Frequency, Actual Deviation from 48 MHz PLL Ratio Output Rise Edge Rate Output Fall Edge Rate Duty Cycle Frequency Stabilization from Power-up (cold start) AC Output Impedance Test Condition/Comments Determined by PLL divider ratio (see m/n below) (48.008 – 48)/48 (14.31818 MHz x 57/17 = 48.008 MHz) Measured from 0.4V to 2.4V Measured from 2.4V to 0.4V Measured on rising and falling edge at 1.5V Assumes full supply voltage reached within 1 ms from power-up. Short cycles exist prior to frequency stabilization. Average value during switching transition. Used for determining series termination value. 25 1 1 45 Min. Typ. 48.008 +167 57/17 4 4 55 3 V/ns V/ns % ms Max. Unit MHz ppm
Zo
Ordering Information
Ordering Code W48C101 Freq. Mask Code -01 Package Name H Package Type 48-pin SSOP (300 mils)
Package Diagram
48-Lead Shrunk Small Outline Package O48
While SLI has reviewed all information herein for accuracy and reliability, Spectra Linear Inc. assumes no responsibility for the use of any circuitry or for the infringement of any patents or other rights of third parties which would result from each use. This product is intended for use in normal commercial applications and is not warranted nor is it intended for use in life support, critical medical instruments, or any other application requiring extended temperature range, high reliability, or any other extraordinary environmental requirements unless pursuant to additional processing by Spectra Linear Inc., and expressed written agreement by Spectra Linear Inc. Spectra Linear Inc. reserves the right to change any circuitry or specification without notice.
Rev 1.0, November 28, 2006
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