PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER GENERAL DESCRIPTION FEATURES The ICS844003I is a 3 differential output LVDS Synthesizer designed to generate Ethernet referHiPerClockS™ ence clock frequencies and is a member of the HiPerClocks™ family of high performance clock solutions from ICS. Using a 31.25MHz or 26.041666MHz, 18pF parallel resonant crystal, the following frequencies can be generated based on the settings of 4 frequency select pins (DIV_SEL[A1:A0], DIV_SEL[B1:B0]): 625MHz, 312.5MHz, 156.25MHz, and 125MHz. The 844003I has 2 output banks, Bank A with 1 differential LVDS output pair and Bank B with 2 differential LVDS output pairs. • Three LVDS outputs on two banks, A Bank with one LVDS pair and B Bank with 2 LVDS output pairs The two banks have their own dedicated frequency select pins and can be independently set for the frequencies mentioned above. The ICS844003I uses ICS’ 3rd generation low phase noise VCO technology and can achieve 1ps or lower typical rms phase jitter, easily meeting Ethernet jitter requirements. The ICS844003I is packaged in a small 24-pin TSSOP package. • 3.3V output supply mode ICS • Using a 31.25MHz or 26.041666MHz crystal, the two output banks can be independently set for 625MHz, 312.5MHz, 156.25MHz or 125MHz • Selectable crystal oscillator interface or LVCMOS/LVTTL single-ended input • VCO range: 560MHz to 700MHz • RMS phase jitter @ 156.25MHz (1.875MHz - 20MHz): 0.63ps (typical) • -40°C to 85°C ambient operating temperature • Available in both standard and lead-free RoHS-compliant packages PIN ASSIGNMENT DIV_SELB0 VCO_SEL MR VDDO_A QA0 nQA0 CLK_ENB CLK_ENA FB_DIV VDDA VDD DIV_SELA0 BLOCK DIAGRAM 24 23 22 21 20 19 18 17 16 15 14 13 DIV_SELB1 VDDO_B QB0 nQB0 QB1 nQB1 XTAL_SEL TEST_CLK XTAL_IN XTAL_OUT GND DIV_SELA1 ICS844003I 24-Lead TSSOP 4.40mm x 7.8mm x 0.92mm package body G Package Top View CLK_ENA Pullup DIV_SELA[1:0] VCO_SEL 1 2 3 4 5 6 7 8 9 10 11 12 Pullup QA0 00 TEST_CLK Pulldown 0 XTAL_IN OSC 1 0 Phase Detector VCO ÷1 01 ÷2 (default) 10 11 ÷4 ÷5 00 01 ÷1 ÷2 10 ÷4 (default) 11 ÷5 nQA0 1 560-700MHz XTAL_OUT XTAL_SEL Pullup QB0 FB_DIV 0 = ÷20 (default) 1 = ÷24 FB_DIV Pulldown nQB0 QB1 nQB1 DIV_SELB[1:0] MR Pulldown CLK_ENB Pullup The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on initial product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications without notice. 844003AGI www.icst.com/products/hiperclocks.html REV. B AUGUST 25, 2005 1 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER TABLE 1. PIN DESCRIPTIONS Number 1 24 Name DIV_SELB0 DIV_SELB1 Type 2 VCO_SEL Input 3 MR Input 4 VDDO_A Power 5, 6 QA0, nQA0 Ouput 7 CLK_ENB Input Pullup 8 CLK_ENA Input Pullup 9 FB_DIV Input Pulldown 10 VDDA Power 11 12 13 14 VDD DIV_SELA0 DIV_SELA1 GND Power 15, 16 XTAL_OUT, XTAL_IN Input 17 TEST_CLK Input 18 XTAL_SEL Input Input Input Power 19, 20 nQB1, QB1 Output 21, 22 nQB0, QB0 Output Description Division select pin for Bank B. Default = Low. Pulldown LVCMOS/LVTTL interface levels. VCO select pin. When Low, the PLL is bypassed and the cr ystal reference or TEST_CLK (depending on XTAL_SEL setting) are passed directly to the Pullup output dividers. Has an internal pullup resistor so the PLL is not bypassed by default. LVCMOS/LVTTL interface levels. Active HIGH Master Reset. When logic HIGH, the internal dividers are reset causing the true outputs Qx to go low and the inver ted outputs nQx Pulldown to go high. When logic LOW, the internal dividers and the outputs are enabled. Has an internal pulldown resistor so the power-up default state of outputs and dividers are enabled. LVCMOS/LVTTL interface levels. Output supply pin for Bank A outputs. Differential output pair. LVDS interface levels. Output enable Bank B. Active High outputs are enable. When logic HIGH, the output pairs on Bank B are enabled. When logic LOW, the output pairs are in a high impedance state. Has an internal pullup resistor so the default power-up state of outputs are enabled. LVCMOS/LVTTL interface levels. Output enable Bank A. Active High output enable. When logic HIGH, the output pair in Bank A is enabled. When logic LOW, the output pair is in a high impedance state. Has an internal pullup resistor so the default power-up state of output is enabled. LVCMOS/LVTTL interface levels. Feedback divide select. When Low (default), the feedback divider is set for ÷20. When HIGH, the feedback divider is set for ÷24. LVCMOS/LVTTL interface levels. Analog supply pin. Core supply pin. Division select pin for Bank A. Default = HIGH. Pullup LVCMOS/LVTTL interface levels. Power supply ground. Parallel resonant cr ystal interface. XTAL_OUT is the output, XTAL_IN is the input. XTAL_IN is also the overdrive pin if you want to overdrive the cr ystal circuit with a single-ended reference clock. Single-ended reference clock input. Has an internal pulldown resistor to Pulldown pull to low state by default. Can leave floating if using the cr ystal interface. LVCMOS/LVTTL interface levels. Cr ystal select pin. Selects between the single-ended TEST_CLK or cr ystal interface. Has an internal pullup resistor so the cr ystal interface is selected Pullup by default. LVCMOS/LVTTL interface levels. Differential output pair. LVDS interface levels. Differential output pair. LVDS interface levels. Power Output supply pin for Bank B outputs. 23 VDDO_B NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values. TABLE 2. PIN CHARACTERISTICS Symbol Parameter CIN Input Capacitance 4 pF RPULLDOWN Input Pulldown Resistor 51 kΩ RPULLUP Input Pullup Resistor 51 kΩ 844003AGI Test Conditions Minimum www.icst.com/products/hiperclocks.html 2 Typical Maximum Units REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER TABLE 3A. BANK A FREQUENCY TABLE Inputs Bank A Output Divider M/N Multiplication Factor QA0/nQA0 Output Frequency (MHz) Crystal Frequency (MHz) DIV_SELA1 DIV_SELA0 FB_DIV Feedback Divider 31.25 0 0 0 20 1 20 625 31.25 0 1 0 20 2 10 312.5 31.25 1 0 0 20 4 5 156.25 31.25 1 1 0 20 5 4 125 26.041666 0 0 1 24 1 24 625 26.041666 0 1 1 24 2 12 312.5 26.041666 1 0 1 24 4 6 156.25 26.041666 1 1 1 24 5 64.8 125 FB_DIV Feedback Divider Bank B Output Divider M/N Multiplication Factor QB0/nQB0 Output Frequency (MHz) TABLE 3B. BANK B FREQUENCY TABLE Inputs Crystal Frequency (MHz) DIV_SELB1 DIV_SELB0 31.25 0 0 0 20 1 20 625 31.25 0 1 0 20 2 10 312.5 31.25 1 0 0 20 4 5 156.25 31.25 1 1 0 20 5 4 125 26.041666 0 0 1 24 1 24 625 26.041666 0 1 1 24 2 12 312.5 26.041666 1 0 1 24 4 6 156.25 26.041666 1 1 1 24 5 4.8 125 844003AGI www.icst.com/products/hiperclocks.html 3 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER TABLE 3C. OUTPUT BANK CONFIGURATION SELECT FUNCTION TABLE Inputs Inputs Outputs Outputs QA DIV_SELB1 DIV_SELB0 0 ÷1 0 0 ÷1 1 ÷2 0 1 ÷2 1 0 ÷4 1 0 ÷4 1 1 ÷5 1 1 ÷5 DIV_SELA1 DIV_SELA0 0 0 QB TABLE 3D. FEEDBACK DIVIDER CONFIGURATION SELECT FUNCTION TABLE Inputs FB_DIV Feedback Divide 0 ÷20 1 ÷24 Enabled Disabled TEST_CLK CLK_ENx nQA0, nQB0:nQB1 QA0, QB0:QB1 FIGURE 1. CLK_EN TIMING DIAGRAM TABLE 3E. CLK_ENA SELECT FUNCTION TABLE Inputs CLK_ENA 844003AGI TABLE 3F. CLK_ENB SELECT FUNCTION TABLE Outputs QA0 Inputs nQA0 CLK_ENB Outputs QB0:QB1 nQB0:nQB1 0 LOW HIGH 0 LOW HIGH 1 Active Active 1 Active Active www.icst.com/products/hiperclocks.html 4 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER ABSOLUTE MAXIMUM RATINGS Supply Voltage, VDD 4.6V Inputs, VI -0.5V to VDD + 0.5V Outputs, IO Continuous Current Surge Current 10mA 15mA Package Thermal Impedance, θJA 70°C/W (0 lfpm) Storage Temperature, TSTG -65°C to 150°C NOTE: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings are stress specifications only. Functional operation of product at these conditions or any conditions beyond those listed in the DC Characteristics or AC Characteristics is not implied. Exposure to absolute maximum rating conditions for extended periods may affect product reliability. TABLE 4A. POWER SUPPLY DC CHARACTERISTICS, VDD = VDDA = VDDO_A = VDDO_B = 3.3V±5%, TA = -40°C TO 85°C Symbol Parameter Test Conditions Minimum Typical Maximum Units VDD Core Supply Voltage 3.135 3.3 3.465 V VDDA Analog Supply Voltage 3.135 3.3 3.465 V VDDO_A, B Output Supply Voltage 3.135 3.3 3.465 V IDD Power Supply Current 99 mA IDDA Analog Supply Current 10 mA IDDO_A, B Output Supply Current 52 mA TABLE 4B. LVCMOS / LVTTL DC CHARACTERISTICS, VDD = VDDA = VDDO_A = VDDO_B = 3.3V±5%, TA = -40°C TO 85°C Symbol Parameter VIH Input High Voltage VIL Input Low Voltage IIH IIL 844003AGI Input High Current Input Low Current Test Conditions Minimum Typical Maximum Units VDD = 3.3V 2 VDD + 0.3 V VDD = 2.5V 1.7 VDD + 0.3 V VDD = 3.3V -0.3 0.8 V VDD = 2.5V VDD = VIN = 3.465V or 2.625V -0.3 0.7 V 150 µA 5 µA TEST_CLK, MR, FB_DIV DIV_SELA1, DIV_SELB0 DIV_SELB1, DIV_SELA0, VCO_SEL, XTAL_SEL, CLK_ENA, CLK_ENB VDD = VIN = 3.465V or 2.625V TEST_CLK, MR, FB_DIV DIV_SELA1, DIV_SELB0 VDD = 3.465V or 2.625V, VIN = 0V DIV_SELB1, DIV_SELA0, VCO_SEL, XTAL_SEL, CLK_ENA, CLK_ENB VDD = 3.465V or 2.625V, VIN = 0V www.icst.com/products/hiperclocks.html 5 -5 µA -150 µA REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER TABLE 4C. LVDS DC CHARACTERISTICS, VDD = VDDA = VDDO_A = VDDO_B = 3.3V±5%, TA = -40°C TO 85°C Symbol Parameter VOD Differential Output Voltage Δ VOD VOD Magnitude Change VOS Offset Voltage Δ VOS VOS Magnitude Change Test Conditions Minimum Typical Maximum Units 40 mV 50 mV Maximum Units 350 0 mV 1.4 0 V TABLE 5. CRYSTAL CHARACTERISTICS Parameter Test Conditions Minimum Mode of Oscillation Frequency Typical Fundamental FB_DIV = ÷20 28 35 MHz FB_DIV = ÷24 23.33 29.16 MHz Equivalent Series Resistance (ESR) 50 Ω Shunt Capacitance 7 pF Drive Level 1 mW Maximum Units NOTE: Characterized using an 18pF parallel resonant cr ystal. TABLE 6. AC CHARACTERISTICS, VDD = VDDA = VDDO_A = VDDO_B = 3.3V±5%, TA = -40°C TO 85°C Symbol Parameter fOUT Output Frequency Range tsk(b) Bank Skew, NOTE 1 tsk(o) Output Skew; NOTE 2, 4 tjit(Ø) t R / tF RMS Phase Jitter (Random); NOTE 3 Output Rise/Fall Time Test Conditions Minimum Typical Output Divider = ÷1 560 700 MHz Output Divider = ÷2 28 0 35 0 MHz Output Divider = ÷4 140 175 MHz Output Divider = ÷5 112 14 0 MHz 3 ps Outputs @ Same Frequency 15 ps Outputs @ Different Frequencies 30 ps 625MHz (1.875MHz - 20MHz) 0.55 ps 312.5MHz (1.875MHz - 20MHz) 0.59 ps 156.25MHz (1.875MHz - 20MHz) 0.63 ps 125MHz (1.875MHz - 20MHz) 0.64 ps 20% to 80% 325 ps odc Output Duty Cycle 50 NOTE 1: Defined as skew within a bank of outputs at the same voltages and with equal load conditions. NOTE 2: Defined as skew between outputs at the same supply voltages and with equal load conditions. Measured at the output differential cross points. NOTE 3: Please refer to the Phase Noise Plots. NOTE 4: This parameter is defined in accordance with JEDEC Standard 65. 844003AGI www.icst.com/products/hiperclocks.html 6 % REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER TYPICAL PHASE NOISE AT 156.25MHZ ➤ 0 -10 -20 -30 10Gb Ethernet Filter 156.25MHz RMS Phase Jitter (Random) 1.875Mhz to 20MHz = 0.63ps (typical) -70 -80 Raw Phase Noise Data -90 -100 -110 -120 -130 -140 -150 -160 ➤ ➤ NOISE POWER dBc Hz -40 -50 -60 -170 -180 -190 100 1k Phase Noise Result by adding 10Gb Ethernet Filter to raw data 10k 100k 1M 10M 100M OFFSET FREQUENCY (HZ) 844003AGI www.icst.com/products/hiperclocks.html 7 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER PARAMETER MEASUREMENT INFORMATION VDD Noise Power Phase Noise Plot SCOPE Qx Power Supply + Float GND - LVDS Phase Noise Mask nQx Offset Frequency f1 f2 RMS Jitter = Area Under the Masked Phase Noise Plot LVDS 3.3V OUTPUT LOAD AC TEST CIRCUIT RMS PHASE JITTER nQA0, nQB0, nQB1 nQx QA0, QB0, QB1 Qx t PW t nQy Qy odc = tsk(o) PERIOD t PW x 100% t PERIOD OUTPUT SKEW OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD nQB0 80% 80% QB0 VSW I N G Clock Outputs nQB1 20% 20% tR tF QB1 tsk(b) OUTPUT RISE/FALL TIME BANK SKEW VDD VDD out ➤ ➤ LVDS 100 DC Input VOD/Δ VOD out LVDS ➤ ➤ DC Input ➤ out out VOS/Δ VOS ➤ DIFFERENTIAL OUTPUT VOLTAGE SETUP 844003AGI OFFSET VOLTAGE SETUP www.icst.com/products/hiperclocks.html 8 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER APPLICATION INFORMATION POWER SUPPLY FILTERING TECHNIQUES As in any high speed analog circuitry, the power supply pins are vulnerable to random noise. The ICS844003I provides separate power supplies to isolate any high switching noise from the outputs to the internal PLL. VDD, VDDA, and VDDOx should be individually connected to the power supply plane through vias, and bypass capacitors should be used for each pin. To achieve optimum jitter performance, power supply isolation is required. Figure 2 illustrates how a 10Ω resistor along with a 10μF and a .01μF bypass capacitor should be connected to each VDDA pin. The 10Ω resistor can also be replaced by a ferrite bead. 3.3V VDD .01μF 10 Ω VDDA .01μF 10μF FIGURE 2. POWER SUPPLY FILTERING CRYSTAL INPUT INTERFACE were determined using a 31.25MHz or 26.041666MHz 18pF parallel resonant crystal and were chosen to minimize the ppm error. The ICS844003I has been characterized with 18pF parallel resonant crystals. The capacitor values shown in Figure 3 below XTAL_OUT C1 22p X1 18pF Parallel Crystal XTAL_IN C2 22p ICS844003I Figure 3. CRYSTAL INPUt INTERFACE 844003AGI www.icst.com/products/hiperclocks.html 9 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER RECOMMENDATIONS FOR UNUSED INPUT AND OUTPUT PINS INPUTS: OUTPUTS: CRYSTAL INPUT: For applications not requiring the use of the crystal oscillator input, both XTAL_IN and XTAL_OUT can be left floating. Though not required, but for additional protection, a 1kΩ resistor can be tied from XTAL_IN to ground. LVDS All unused LVDS output pairs can be either left floating or terminated with 100Ω across. If they are left floating, we recommend that there is no trace attached. TEST_CLK INPUT: For applications not requiring the use of the test clock, it can be left floating. Though not required, but for additional protection, a 1kΩ resistor can be tied from the TEST_CLK to ground. LVCMOS CONTROL PINS: All control pins have internal pull-ups or pull-downs; additional resistance is not required but can be added for additional protection. A 1kΩ resistor can be used. 3.3V LVDS DRIVER TERMINATION A general LVDS interface is shown in Figure 4. In a 100Ω differential transmission line environment, LVDS drivers require a matched load termination of 100Ω across near the receiver input. 3.3V 3.3V LVDS + R1 100 - 100 Ohm Differential Transmission Line FIGURE 4. TYPICAL LVDS DRIVER TERMINATION 844003AGI www.icst.com/products/hiperclocks.html 10 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER RELIABILITY INFORMATION TABLE 7. θJAVS. AIR FLOW TABLE FOR 24 LEAD TSSOP θJA by Velocity (Meters per Second) Multi-Layer PCB, JEDEC Standard Test Boards 0 1 2.5 70°C/W 65°C/W 62°C/W TRANSISTOR COUNT The transistor count for ICS844003I is: 3394 844003AGI www.icst.com/products/hiperclocks.html 11 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. PACKAGE OUTLINE - G SUFFIX FOR ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER 24 LEAD TSSOP TABLE 8. PACKAGE DIMENSIONS SYMBOL Millimeters Minimum N Maximum 24 A -- 1.20 A1 0.05 0.15 A2 0.80 1.05 b 0.19 0.30 c 0.09 0.20 D 7.70 E E1 7.90 6.40 BASIC 4.30 e 4.50 0.65 BASIC L 0.45 0.75 α 0° 8° aaa -- 0.10 Reference Document: JEDEC Publication 95, MO-153 844003AGI www.icst.com/products/hiperclocks.html 12 REV. B AUGUST 25, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS844003I FEMTOCLOCKS™CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER TABLE 9. ORDERING INFORMATION Part/Order Number Marking Package Shipping Packaging Temperature ICS844003AGI ICS844003AGI 24 Lead TSSOP tube -40°C to 85°C ICS844003AGIT ICS844003AGI 24 Lead 2500 tape & reel -40°C to 85°C ICS844003AGILF TBD 24 Lead "Lead-Free" TSSOP tube -40°C to 85°C ICS844003AGITLF TBD 24 Lead "Lead-Free" TSSOP 2500 tape & reel -40°C to 85°C NOTE: Par ts that are ordered with an "LF" suffix to the par t number are the Pb-Free configuration and are RoHS compliant. The aforementioned trademarks, HiPerClockS and FemtoClocks are trademarks of Integrated Circuit Systems, Inc. or its subsidiaries in the United States and/or other countries. While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (ICS) assumes no responsibility for either its use or for infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial and industrial applications. Any other applications such as those requiring high reliability or other extraordinary environmental requirements are not recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for use in life support devices or critical medical instruments. 844003AGI www.icst.com/products/hiperclocks.html 13 REV. B AUGUST 25, 2005