PRELIMINARY W133 Spread Spectrum System Frequency Synthesizer Features CPU Output Jitter: ...................................................... 250 ps • Maximized EMI suppression using Cypress’s spread spectrum technology • Intel CK98 Specification compliant • 0.5% downspread outputs deliver up to 10 dB lower EMI • Four skew-controlled copies of CPU output • Eight copies of PCI output (synchronous w/CPU output) • Four copies of 66-MHz fixed frequency 3.3V clock • Two copies of CPU/2 outputs for synchronous memory reference • Three copies of 16.67-MHz IOAPIC clock, synchronous to CPU clock • One copy of 48-MHz USB output • Two copies of 14.31818-MHz reference clock • Programmable to 133- or 100-MHz operation • Power management control pins for clock stop and shut down • Available in 56-pin SSOP Key Specifications CPUdiv2 Output Jitter:.................................................250 ps 48 MHz, 3V66, PCI, IOAPIC Output Jitter: .................. 500 ps CPU0:3, CPUdiv2_ 0:1 Output Skew: ......................... 175 ps PCI_F, PCI1:7 Output Skew: .......................................500 ps 3V66_0:3, IOAPIC0:2 Output Skew; ...........................250 ps CPU to 3V66 Output Offset: ............. 0.0–1.5 ns (CPU leads) 3V66 to PCI Output Offset:.............. 1.5–4.0 ns (3V66 leads) CPU to IOAPIC Output Offset: ......... 1.5–4.0 ns (CPU leads) Logic inputs, except SEL133/100#, have 250-kΩ pull-up resistors. Table 1. Pin Selectable Frequency[1] SEL133/100# 1 0 CPU0:3 (MHz) 133 MHz 100 MHz PCI 33.3 MHz 33.3 MHz Note: 1. See Table 2 for complete mode selection details. Supply Voltages: ...................................... VDDQ3 = 3.3V±5% VDDQ2 = 2.5V±5% Block Diagram X1 X2 Pin Configuration 2 XTAL OSC REF0:1 CPU_STOP# STOP Clock Logic 4 CPU0:3 SEL0 SEL1 CPUdiv2_0:1 PLL 1 SEL133/100# ÷2/÷1.5 STOP Clock Logic 4 3V66_0:3 1 PCI_F ÷2 PWRDWN# 7 STOP Clock Logic PCI1:7 PCI_STOP# Power Down Logic 3 ÷2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 W133 2 ÷2 SPREAD# GND REF0 REF1 VDDQ3 X1 X2 GND PCI_F PCI1 VDDQ3 PCI2 PCI3 GND PCI4 PCI5 VDDQ3 PCI6 PCI7 GND GND 3V66_0 3V66_1 VDDQ3 GND 3V66_2 3V66_3 VDDQ3 SEL133/100# 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 VDDQ2 IOAPIC2 IOAPIC1 IOAPIC0 GND VDDQ2 CPUdiv2_1 CPUdiv2_0 GND VDDQ2 CPU3 CPU2 GND VDDQ2 CPU1 CPU0 GND VDDQ3 GND PCI_STOP# CPU_STOP# PWRDWN# SPREAD# SEL1 SEL0 VDDQ3 48MHz GND IOAPIC0:2 Three-state Logic 1 PLL2 Cypress Semiconductor Corporation 48MHz • 3901 North First Street • San Jose • CA 95134 • 408-943-2600 October 13, 1999, rev. ** PRELIMINARY W133 Pin Definitions Pin No. 41, 42, 45, 46 Pin Type O 49,50 O PCI1:7 9, 11, 12, 14, 15, 17, 18 O PCI_F 8 O REF0:1 2, 3 O 53, 54, 55 O 30 O 21, 22, 25, 26 O 32, 33 I SEL133/100# 28 I X1 5 I X2 6 O SPREAD# 34 I PWRDWN# 35 I CPU_STOP# 36 I PCI_STOP# 37 I VDDQ3 4, 10, 16, 23, 27, 31, 39 P VDDQ2 43, 47, 51, 56 P 1, 7, 13, 19, 20, 24, 29, 38, 40, 44, 48, 52 G Pin Name CPU0:3 CPUdiv2_ 0:1 IOAPIC0:2 48MHz 3V66_0:3 SEL0:1 GND Pin Description CPU Clock Outputs 0 through 3: These four CPU clocks run at a frequency set by SEL133/100#. Output voltage swing is set by the voltage applied to VDDQ2. Synchronous Memory Reference Clock Output 0 through 1: Reference clock for Direct RDRAM clock generators running at 1/2 CPU clock frequency. Output voltage swing is set by the voltage applied to VDDQ2. PCI Clock Outputs 1 through 7: These seven PCI clock outputs run synchronously to the CPU clock. Voltage swing is set by the power connection to VDDQ3. PCI1:7 outputs are stopped when PCI _STOP# is held LOW. PCI_F (PCI Free-running): This PCI clock output runs synchronously to the CPU clock. Voltage swing is set by the power connection to VDDQ3. PCI_F is not affected by the state of PCI_STOP#. 14.318-MHz Reference Clock Output: 3.3V copies of the 14.318-MHz reference clock. I/O APIC Clock Output: Provides 16.67-MHz fixed frequency. The output voltage swing is set by the power connection to VDDQ2. 48-MHz Output: Fixed 48-MHz USB output. Output voltage swing is controlled by voltage applied to VDDQ3. 66-MHz Output 0 through 3: Fixed 66-MHz outputs. Output voltage swing is controlled by voltage applied to VDDQ3. Mode Select Input 0 through 1: 3.3V LVTTL-compatible input for selecting clock output modes. Frequency Selection Input: 3.3V LVTTL-compatible input that selects CPU output frequency as shown in Table 1. Crystal Connection or External Reference Frequency Input: Connect to either a 14.318-MHz crystal or an external reference signal. Crystal Connection: An output connection for an external 14.318-MHz crystal. If using an external reference, this pin must be left unconnected. Active LOW Spread Spectrum Enable: 3.3V LVTTL-compatible input that enables spread spectrum mode when held LOW. Active LOW Power Down Input: 3.3V LVTTL-compatible asynchronous input that requests the device to enter power-down mode. Active LOW CPU Clock Stop: 3.3V LVTTL-compatible asynchronous input that stops all CPU and 3V66 clocks when held LOW. CPUdiv2 outputs are unaffected by this input. Active LOW PCI Clock Stop: 3.3V LVTTL-compatible asynchronous input that stops all PCI outputs except PCI_F when held LOW. Power Connection: Power supply for PCI output buffers, 48-MHz USB output buffer, Reference output buffers, 3V66 output buffers, core logic, and PLL circuitry. Connect to 3.3V supply. Power Connection: Power supply for IOAPIC, CPU, and CPUdiv2 output buffers. Connect to 2.5V supply. Ground Connection: Connect all ground pins to the common system ground plane. Overview All CPU, PCI, and IOAPIC clocks can be synchronously modulated for spread spectrum operations. Cypress employs proprietary techniques that provide the maximum EMI reduction while minimizing the clock skews that could reduce system timing margins. Spread Spectrum modulation is enabled by the active LOW control signal SPREAD#. The W133 is designed to provide the essential frequency sources to work with advanced multiprocessing Intel® architecture platforms. Split voltage supply signaling provides 2.5V and 3.3V clock frequencies operating up to 133 MHz. The W133 also includes power management control inputs. By using these inputs, system logic can stop CPU and/or PCI clocks or power down the entire device to conserve system power. From a low-cost 14.31818-MHz reference crystal oscillator, the W133 generates 2.5V clock outputs to support CPUs, core logic chip set, and Direct RDRAM clock generators. It also provides skew-controlled PCI and IOAPIC clocks synchronous to CPU clock, 48-MHz Universal Serial Bus (USB) clock, and replicates the 14.31818-MHz reference clock. 2 PRELIMINARY W133 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% downspread. 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 dB = 6.5 + 9*log10(P) + 9*log10(F) EMI Reduction Spread Spectrum Enabled NonSpread Spectrum Time Figure 2. Modulation Waveform Profile 3 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 100% 90% 80% 70% 60% 50% 40% 30% 20% 100% 80% 60% 40% 20% 0% –20% –40% –60% –80% –100% 10% Frequency Shift Figure 1. Typical Clock and SSFTG Comparison PRELIMINARY W133 Mode Selection Functions The W133 supports the following operating modes controlled through the SEL133/100#, SEL0, and SEL1 inputs. Table 2. Select Functions SEL133/100# SEL1 SEL0 0 0 0 All Outputs Three-State Function 0 0 1 (Reserved) 0 1 0 Active 100 MHz, 48 MHz PLL Inactive 0 1 1 Active 100 MHz, 48 MHz PLL Active 1 0 0 Test Mode 1 0 1 (Reserved) 1 1 0 Active 133 MHz, 48 MHz PLL Inactive 1 1 1 Active 133 MHz, 48 MHz PLL Active Table 3. Truth Table SEL 133/100# SEL1 SEL0 CPU CPUdiv2 3V66 PCI 48MHz REF IOAPIC Notes 0 0 0 HI-Z HI-Z HI-Z HI-Z HI-Z HI-Z HI-Z 2 0 0 1 n/a n/a n/a n/a n/a n/a n/a 0 1 0 100 MHz 50 MHz 66 MHz 33 MHz HI-Z 14.318 MHz 16.67 MHz 3 0 1 1 100 MHz 50 MHz 66 MHz 33 MHz 48 MHz 14.318 MHz 16.67 MHz 4, 7, 8 1 0 0 TCLK/2 TCLK/4 TCLK/4 TCLK/8 TCLK/2 1 0 1 n/a n/a n/a n/a n/a 1 1 0 133 MHz 66 MHz 66 MHz 33 MHz HI-Z 14.318 MHz 16.67 MHz 3 1 1 1 133 MHz 66 MHz 66 MHz 33 MHz 48 MHz 14.318 MHz 16.67 MHz 4, 7, 8 TCLK TCLK16 n/a n/a 5, 6 Table 4. Maximum Supply Current Max. 2.5V supply consumption Max. discrete cap loads, VDDQ2=2.625V All static inputs=VDDQ3 or GND Max. 3.3V supply consumption Max. discrete cap loads, VDDQ3=3.465V or GND Powerdown Mode (PWRDWN#=0) 100 µA 200 µA FUll Active 100MHz SEL133/100#=0 SEL1, 0=11 CPU_STOP#, PCI_STOP#=1 75 mA 160 mA Full Active 133MHz SEL133/100#=0 SEL1, 0=11 CPU_STOP#, PCI_STOP#=1 90 mA 160 mA Condition Notes: 2. Provided for board level “bed of nails” testing. 3. 48-MHz PLL disabled to reduce component jitter. 4. “Normal” mode of operation. 5. TCLK is a test clock over driven on the X1 input during test mode. TCLK mode is based on 133-MHz CPU select logic. 6. Required for DC output impedance verification. 7. Range of reference frequency is min.=14.316, nominal = 14.31818 MHz, max.=14.32 MHz. 8. Frequency accuracy of 48 MHz is +167 PPM to match USB default. 4 PRELIMINARY W133 Table 5. Clock Enable Configuration[9, 10, 11, 12, 13, 14] CPU_STOP# PWRDWN# PCI_STOP# CPU CPUdiv2 IOAPIC 3V66 PCI PCI_F REF, 48MHz OSC. VCOs X 0 X LOW LOW LOW LOW LOW LOW LOW OFF OFF 0 1 0 LOW ON ON LOW LOW ON ON ON ON 0 1 1 LOW ON ON LOW ON ON ON ON ON 1 1 0 ON ON ON ON LOW ON ON ON ON 1 1 1 ON ON ON ON ON ON ON ON ON Table 6. Power Management State Transition [15, 16] Latency Signal Signal State CPU_STOP# 0 (disabled) 1 1 (enabled) 1 PCI_STOP# PWRDWN# No. of rising edges of PCI Clock 0 (disabled) 1 1 (enabled) 1 1 (normal operation) 3 ms 0 (power down) 2 max. Timing Diagrams CPU_STOP# Timing Diagram[17, 18, 19, 20, 21, 22] CPU (internal) PCI CPU_STOP# PCI_STOP# HI PWRDWN# HI CPU (external) 3V66 Notes: 9. LOW means outputs held static LOW as per latency requirement below. 10. ON means active. 11. PWRDWN# pulled LOW, impacts all outputs including REF and 48-MHz outputs. 12. All 3V66 as well as all CPU clocks stop cleanly when CPU_STOP# is pulled LOW. 13. CPUdiv2, IOAPIC, REF, 48MHz signals are not controlled by the CPU_STOP# functionality and are enabled in all conditions except PWRDWN#=LOW. 14. An “x” indicates a “don’t care” condition. 15. Clock on/off latency is defined in the number of rising edges of the free-running PCI clock between when the clock disable goes LOW/HIGH to when the first valid clock comes out of the device. 16. Power up latency is from when PWRDWN# goes inactive (HIGH) to when the first valid clocks are driven from the device. 17. All internal timing is referenced to the CPU clock. 18. The internal label means inside the chip and is a reference only. This in fact may not be the way that the control is designed. 19. CPU_STOP# signal is an input signal that must be made synchronous to free-running PCI_F. 20. 3V66 clocks also stop/start before. 21. PWRDWN# and PCI_STOP# are shown in a HIGH state. 22. Diagrams shown with respect to 133 MHz. Similar operation when CPU clock is 100 MHz. 5 PRELIMINARY Timing Diagrams (continued) PCI_STOP# Timing Diagram[17, 18, 22, 23, 24, 25] CPU PCI (internal) PCI_STOP# CPU_STOP# HI PWRDWN# HI PCI_F (external) PCI (external) PWRDWN# Timing Diagram[17, 22, 26, 27] CPU (internal) PCI (internal) PWRDWN# CPU (external) PCI (external) VCO Crystal Notes: 23. PCI_STOP# signal is an input signal that must be made synchronous to PCI_F output. 24. All other clocks continue to run undisturbed. 25. PWRDWN# and CPU_STOP# are shown in a HIGH state. 26. The internal label means inside the chip and is a reference only. This in fact may not be the way that the control is designed. 27. PWRDWN is an asynchronous input and metastable conditions could exist. This signal is required to be synchronized. 28. The shaded sections on the VCO and the Crystal signals indicate an active clock. 6 W133 PRELIMINARY W133 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 IDD-3.3V Combined 3.3V Supply Current CPU0:3 =133 MHz[29] 160 mA IDD-2.5 Combined 2.5V Supply Current CPU0:3 =133 MHz[29] 90 mA GND – 0.3 0.8 V 2.0 VDD + 0.3 V –25 µA Logic Inputs (All referenced to VDDQ3 = 3.3V) Input Low Voltage VIL VIH IIL Input High Voltage [30] Input Low Current [30] IIH Input High Current 10 µA IIL Input Low Current, SEL133/100#[30] –5 µA 5 µA Max. Unit 50 mV IIH [30] Input High Current, SEL133/100# Clock Outputs CPU, CPUdiv2, IOAPIC (Referenced to VDDQ2) Test Condition Min. VOL Output Low Voltage IOL = 1 mA VOH Output High Voltage IOH = –1 mA 2.2 IOL Output Low Current VOL = 1.25V 45 IOH Output High Current VOH = 1.25V Typ. V 65 100 mA 45 65 100 mA Min. Typ. Max. Unit 50 mV 48MHz, REF (Referenced to VDDQ3) VOL Output Low Voltage IOL = 1 mA VOH Output High Voltage IOH = –1 mA 3.1 IOL Output Low Current VOL = 1.5V 45 65 100 mA IOH Output High Current VOH = 1.5V 45 65 100 mA Min. Typ. Max. Unit 50 mV PCI, 3V66 (Referenced to VDDQ3) Test Condition Test Condition V VOL Output Low Voltage IOL = 1 mA VOH Output High Voltage IOH = –1 mA 3.1 IOL Output Low Current VOL = 1.5V 70 100 145 mA IOH Output High Current VOH = 1.5V 65 95 135 mA Notes: 29. All clock outputs loaded with 6" 60Ω transmission lines with 20-pF capacitors. 30. W133 logic inputs have internal pull-up devices, except SEL133/100# (pull-ups not CMOS level). 7 V PRELIMINARY W133 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[31] CLOAD Load Capacitance, Imposed on External Crystal[32] CIN,X1 X1 Input Capacitance[33] Pin X2 unconnected 1.65 V 18 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 3.3V AC Electrical Characteristics TA = 0°C to +70°C, VDDQ3 = 3.3V±5%,VDDQ2 = 2.5V± 5%, fXTL = 14.31818 MHz Spread Spectrum function turned off AC clock parameters are tested and guaranteed over stated operating conditions using the stated lump capacitive load at the clock output.[34] 3V66 Clock Outputs, 3V66_0:3 (Lump Capacitance Test Load = 30 pF) Parameter Description Test Condition/Comments Min. Typ. Max. 66.6 Unit f Frequency Note 35 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. 15 MHz Ω Notes: 31. X1 input threshold voltage (typical) is VDD/2. 32. The W133 contains an internal crystal load capacitor between pin X1 and ground and another between pin X2 and ground. Total load placed on crystal is 18 pF; this includes typical stray capacitance of short PCB traces to crystal. 33. X1 input capacitance is applicable when driving X1 with an external clock source (X2 is left unconnected). 34. Period, jitter, offset, and skew measured on rising edge at 1.5V. 35. 3V66 is CPU/2 for CPU =133 MHz and (2 x CPU)/3 for CPU = 100 MHz. 8 PRELIMINARY W133 PCI Clock Outputs, PCI_F and PCI1:7 (Lump Capacitance Test Load = 30 pF) Parameter Description Test Condition/Comments Min. [36] 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 tF Output Fall Edge Rate Measured from 2.4V to 0.4V tD Duty Cycle Measured on rising and falling edge at 1.5V tJC Jitter, Cycle-to-Cycle tSK 1 4 V/ns 1 4 V/ns 45 55 % Measured on rising edge at 1.5V. Maximum difference of cycle time between two adjacent cycles. 500 ps Output Skew Measured on rising edge at 1.5V. 500 ps tO 3V66 to PCI Clock Skew Covers all 3V66/PCI outputs. Measured on rising edge at 1.5V. 3V66 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 REF Clock Outputs, REF0:1 (Lump Capacitance Test Load = 20 pF) Parameter Description Test Condition/Comments Min. Typ. Max. Unit f Frequency, Actual Frequency generated by crystal oscillator 14.318 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. Ω 25 48-MHZ Clock Output (Lump Capacitance Test Load = 20 pF) Parameter Description Test Condition/Comments Min. Typ. Max. Unit f Frequency, Actual Determined by PLL divider ratio (see m/n below) fD Deviation from 48 MHz (48.008 – 48)/48 m/n PLL Ratio (14.31818 MHz x 57/17 = 48.008 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. Note: 36. PCI clock is CPU/4 for CPU = 133 MHz and CPU/3 for CPU = 100 MHz. 9 48.008 MHz +167 ppm 57/17 25 Ω PRELIMINARY W133 2.5V AC Electrical Characteristics TA = 0°C to +70°C, VDDQ3 = 3.3V±5%, V DDQ2= 2.5V±5% fXTL = 14.31818 MHz Spread Spectrum function turned off AC clock parameters are tested and guaranteed over stated operating conditions using the stated lump capacitive load at the clock output.[37] CPU Clock Outputs, CPU0:3 (Lump Capacitance Test Load = 20 pF) CPU = 133MHz Parameter Description Test Condition/Comments CPU = 100MHz Min. Typ. Max. Min. Typ. Max. Unit tP Period Measured on rising edge at 1.25V 7.5 tH High Time Duration of clock cycle above 2.0V 1.87 3.0 ns tL Low Time Duration of clock cycle below 0.4V 1.67 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. 250 250 ps tSK Output Skew Measured on rising edge at 1.25V 175 175 ps 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 3 ms Zo AC Output Impedance Average value during switching transition. Used for determining series termination value. 7.65 10 10.2 ns Ω 20 20 CPU = 133 MHz CPU = 100 MHz CPUdiv2 Clock Outputs, CPUdiv2_0:1 (Lump Capacitance Test Load = 20 pF) Parameter Description Test Condition/Comments Min. Typ. Max. Min. Period Measured on rising edge at 1.25V 15 tH High Time Duration of clock cycle above 2.0V 5.25 7.5 ns tL Low Time Duration of clock cycle below 0.4V 5.05 7.3 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. 250 250 ps tSK Output Skew Measured on rising edge at 1.25V 175 175 ps 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 3 ms Zo AC Output Impedance Average value during switching transition. Used for determining series termination value. Note: 37. Period, Jitter, offset, and skew measured on rising edge at 1.25V. 10 15.3 Typ. Max. Unit tP 20 20 20.4 20 ns Ω PRELIMINARY W133 IOAPIC Clock Outputs, IOAPIC0:2 (Lump Capacitance Test Load = 20 pF) Parameter Description Test Condition/Comments f Frequency Note 38 tR Output Rise Edge Rate Measured from 0.4V to 2.0V tF Output Fall Edge Rate Measured from 2.0V to 0.4V tD Duty Cycle Measured on rising and falling 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. Ordering Information W133 Package Name H Typ Max 16.67 Note: 38. IOAPIC clock is CPU/8 for CPU = 133 MHz and CPU/6 for CPU = 100 MHz. Ordering Code Min Package Type 56-pin SSOP (300 mils) Intel is a registered trademark of Intel Corporation. Document #: 38-00823 11 1 Unit MHz 4 V/ns 1 4 V/ns 45 55 % 3 ms 20 Ω PRELIMINARY W133 Package Diagram 56-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.