PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. GENERAL DESCRIPTION FEATURES The ICS843251I-12 is a 10Gb Ethernet Clock Generator and a member of the HiPerClocksTM HiPerClockS™ family of high performance devices from ICS. The ICS843251I-12 uses an 18pF parallel resonant crystal over the range of 23.2MHz - 30MHz. For Ethernet applications, a 25MHz crystal is used. The device has excellent <1ps phase jitter performance, over the 1.875MHz - 20MHz integration range. The ICS843251I-12 is packaged in a small 8-pin TSSOP, making it ideal for use in systems with limited board space. • One Differential LVPECL output ICS • Crystal oscillator interface, 18pF parallel resonant crystal (23.2MHz - 30MHz) • Output frequency range: 290MHz - 750MHz • VCO range: 580MHz - 750MHz • RMS phase jitter @ 312.5MHz, using a 25MHz crystal (1.875MHz - 20MHz): 0.36ps (typical) • 3.3V or 2.5V operating supply • -40°C to 85°C ambient operating temperature • Available in both standard and lead-free RoHS-compliant packages COMMON CONFIGURATION TABLE Inputs Output Frequency (MHz) Crystal Frequency (MHz) FREQ_SEL M N Multiplication Value M/N 25 0 25 1 25 625 25 1 25 2 12.5 312.5 BLOCK DIAGRAM FREQ_SEL Pullup XTAL_IN OSC XTAL_OUT PIN ASSIGNMENT Phase Detector VCO 580MHz - 750MHz FREQ_SEL N 0 ÷1 1 ÷2 Q nQ VCCA VEE XTAL_OUT XTAL_IN 1 2 3 4 8 7 6 5 VCC Q nQ FREQ_SEL ICS843251I-12 8-Lead TSSOP 4.4mm x 3.0mm x 0.925mm package body G Package Top View M = ÷25 (fixed) 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. 843251BGI-12 www.icst.com/products/hiperclocks.html REV. A JANUARY 10, 2006 1 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. TABLE 1. PIN DESCRIPTIONS Number Name 1 VCCA Power Analog supply pin. 2 Power 5 VEE XTAL_OUT, XTAL_IN FREQ_SEL Negative supply pin. Crystal oscillator interface. XTAL_IN is the input, XTAL_OUT is the output. Frequency select pin. LVCMOS/LVTTL interface levels. 6, 7 nQ, Q Output Differential clock outputs. LVPECL interface levels. 8 VCC Power Core supply pin. 3, 4 Type Description Input Input Pullup NOTE: Pullup refers to internal input resistors. See Table 2, Pin Characteristics, for typical values. TABLE 2. PIN CHARACTERISTICS Symbol Parameter CIN Input Capacitance 4 pF RPULLUP Input Pullup Resistor 51 kΩ 843251BGI-12 Test Conditions Minimum www.icst.com/products/hiperclocks.html 2 Typical Maximum Units REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC Inputs, VI 4.6V -0.5V to VCC + 0.5V Outputs, IO Continuous Current Surge Current 50mA 100mA Package Thermal Impedance, θJA 101.7°C/W (0 mps) 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 3A. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCA = 3.3V±5%, TA = -40°C TO 85°C Symbol Parameter Minimum Typical Maximum Units VCC Core Supply Voltage Test Conditions 3.135 3.3 3.465 V VCCA Analog Supply Voltage 3.135 3.3 3.465 IEE Power Supply Current TBD V mA TABLE 3B. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCA = 2.5V±5%, TA = -40°C TO 85°C Symbol Parameter Test Conditions Minimum Typical Maximum Units VCC Core Supply Voltage 2.375 2.5 2.625 V VCCA Analog Supply Voltage 2.375 2.5 2.625 V IEE Power Supply Current TBD mA TABLE 3C. LVCMOS/LVTTL DC CHARACTERISTICS, VCC = VCCA = 3.3V±5% OR 2.5V±5%, TA = -40°C TO 85°C Symbol Parameter VIH Input High Voltage VIL Input Low Voltage Test Conditions Minimum VCC = 3.3V Maximum Units 2 VCC + 0.3 V VCC = 2.5V 1.7 VCC + 0.3 V VCC = 3.3V -0.3 0.8 V VCC = 2.5V -0.3 0.7 V IIH Input High Current VCC = VIN = 3.465V or 2.625V IIL Input Low Current VCC = 3.465V or 2.625V, VIN = 0V 843251BGI-12 www.icst.com/products/hiperclocks.html 3 Typical 5 -150 µA µA REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. TABLE 3D. LVPECL DC CHARACTERISTICS, VCC = VCCA = 3.3V±5% OR 2.5V±5%, TA = -40°C TO 85°C Symbol Parameter Maximum Units VOH Output High Voltage; NOTE 1 Test Conditions Minimum VCC - 1.4 Typical VCC - 0.9 V VOL Output Low Voltage; NOTE 1 VCC - 2.0 VCC - 1.7 V VSWING Peak-to-Peak Output Voltage Swing 0.6 1.0 V Maximum Units NOTE 1: Outputs terminated with 50Ω to VCC - 2V. TABLE 4. CRYSTAL CHARACTERISTICS Parameter Test Conditions Minimum Mode of Oscillation Typical Fundamental Frequency 23.2 Equivalent Series Resistance (ESR) Shunt Capacitance Drive Level 30 MHz TBD Ω 7 pF TBD mW Maximum Units TABLE 5A. AC CHARACTERISTICS, VCC = VCCA = 3.3V±5%, TA = -40°C TO 85°C Symbol fOUT t jit(Ø) t R / tF Parameter Output Frequency RMS Phase Jitter ( Random); NOTE 1 Output Rise/Fall Time Test Conditions Minimum Typical F_SEL = 1 312.5 MHz F_SEL = 0 312.5MHz @ Integration Range: 1.875MHz - 20MHz 20% to 80% 625 MHz 0.36 ps 325 ps 50 % odc Output Duty Cycle NOTE 1: Please refer to the Phase Noise Plots following this section. TABLE 5B. AC CHARACTERISTICS, VCC = VCCA = 2.5V±5%, TA = -40°C TO 85°C Symbol Parameter fOUT Output Frequency t jit(Ø) tR / tF RMS Phase Jitter ( Random); NOTE 1 Output Rise/Fall Time Test Conditions Minimum Maximum Units F_SEL = 1 312.5 MHz F_SEL = 0 312.5MHz @ Integration Range: 1.875MHz - 20MHz 20% to 80% 625 MHz 0.38 ps 325 ps 50 % odc Output Duty Cycle NOTE 1: Please refer to the Phase Noise Plots following this section. 843251BGI-12 Typical www.icst.com/products/hiperclocks.html 4 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. TYPICAL PHASE NOISE AT 312.5MHZ (3.3V) ➤ 0 -10 -20 10GigE Filter -30 312.5MHz -40 RMS Phase Jitter (Random) 1.875Mhz to 20MHz = 0.36ps (typical) -50 -60 -70 Raw Phase Noise Data -90 ➤ NOISE POWER dBc Hz -80 -100 -110 -120 -130 -140 -150 ➤ -160 Phase Noise Result by adding 10GigE Filter to raw data -170 -180 -190 100 1k 10k 100k 1M 10M 100M OFFSET FREQUENCY 843251BGI-12 www.icst.com/products/hiperclocks.html 5 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. PARAMETER MEASUREMENT INFORMATION 2V 2V VCC, VCCA Qx SCOPE VCC, VCCA LVPECL Qx SCOPE LVPECL nQx nQx VEE VEE -1.3V ± 0.165V -0.5V ± 0.125V LVPECL 3.3V OUTPUT LOAD AC TEST CIRCUIT LVPECL 2.5V OUTPUT LOAD AC TEST CIRCUIT Noise Power Phase Noise Plot nQ Q Phase Noise Mask t PW t Offset Frequency f1 f2 odc = PERIOD t PW x 100% t PERIOD RMS Jitter = Area Under the Masked Phase Noise Plot RMS PHASE JITTER OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD 80% 80% VSW I N G Clock Outputs 20% 20% tR tF OUTPUT RISE/FALL TIME 843251BGI-12 www.icst.com/products/hiperclocks.html 6 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. APPLICATION INFORMATION POWER SUPPLY FILTERING TECHNIQUES As in any high speed analog circuitry, the power supply pins are vulnerable to random noise. The ICS843251I-12 provides separate power supplies to isolate any high switching noise from the outputs to the internal PLL. VCC and VCCA 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 1 illustrates how a 10Ω resistor along with a 10μF and a .01μF bypass capacitor should be connected to each VCCA pin. The 10Ω resistor can also be replaced by a ferrite bead. 3.3V or 2.5V VCC .01μF 10Ω VCC .01μF 10μF FIGURE 1. POWER SUPPLY FILTERING CRYSTAL INPUT INTERFACE 25MHz, 18pF parallel resonant crystal and were chosen to minimize the ppm error. The optimum C1 and C2 values can be slightly adjusted for different board layouts. The ICS843251I-12 has been characterized with 18pF parallel resonant crystals. The capacitor values (TBD), C1 and C2, shown in Figure 2 below were determined using a XTAL_IN C1 X1 Crystal XTAL_OUT C2 Figure 2. CRYSTAL INPUt INTERFACE 843251BGI-12 www.icst.com/products/hiperclocks.html 7 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. TERMINATION FOR 3.3V LVPECL OUTPUT The clock layout topology shown below is a typical termination for LVPECL outputs. The two different layouts mentioned are recommended only as guidelines. designed to drive 50Ω transmission lines. Matched impedance techniques should be used to maximize operating frequency and minimize signal distortion. Figures 3A and 3B show two different layouts which are recommended only as guidelines. Other suitable clock layouts may exist and it would be recommended that the board designers simulate to guarantee compatibility across all printed circuit and clock component process variations. FOUT and nFOUT are low impedance follower outputs that generate ECL/LVPECL compatible outputs. Therefore, terminating resistors (DC current path to ground) or current sources must be used for functionality. These outputs are 3.3V Zo = 50Ω 125Ω FOUT 125Ω FIN Zo = 50Ω Zo = 50Ω FOUT 50Ω RTT = 1 Z ((VOH + VOL) / (VCC – 2)) – 2 o VCC - 2V Zo = 50Ω RTT 84Ω FIGURE 3A. LVPECL OUTPUT TERMINATION 843251BGI-12 FIN 50Ω 84Ω FIGURE 3B. LVPECL OUTPUT TERMINATION www.icst.com/products/hiperclocks.html 8 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. TERMINATION FOR 2.5V LVPECL OUTPUT Figure 4A and Figure 4B show examples of termination for 2.5V LVPECL driver. These terminations are equivalent to terminating 50Ω to VCC - 2V. For VCC = 2.5V, the VCC - 2V is very close to ground level. The R3 in Figure 4B can be eliminated and the termination is shown in Figure 4C. 2.5V VCC=2.5V 2.5V 2.5V VCC=2.5V R1 250 Zo = 50 Ohm R3 250 + Zo = 50 Ohm + Zo = 50 Ohm - Zo = 50 Ohm 2,5V LVPECL Driv er - R1 50 2,5V LVPECL Driv er R2 62.5 R2 50 R4 62.5 R3 18 FIGURE 4B. 2.5V LVPECL DRIVER TERMINATION EXAMPLE FIGURE 4A. 2.5V LVPECL DRIVER TERMINATION EXAMPLE 2.5V VCC=2.5V Zo = 50 Ohm + Zo = 50 Ohm 2,5V LVPECL Driv er R1 50 R2 50 FIGURE 4C. 2.5V LVPECL TERMINATION EXAMPLE 843251BGI-12 www.icst.com/products/hiperclocks.html 9 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. RELIABILITY INFORMATION TABLE 6. θJAVS. AIR FLOW TABLE FOR 8 LEAD TSSOP θJA by Velocity (Meters per Second) Multi-Layer PCB, JEDEC Standard Test Boards 0 1 2.5 101.7°C/W 90.5°C/W 89.8°C/W TRANSISTOR COUNT The transistor count for ICS843251I-12 is: 2377 843251BGI-12 www.icst.com/products/hiperclocks.html 10 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. PACKAGE OUTLINE - G SUFFIX FOR 8 LEAD TSSOP TABLE 7. PACKAGE DIMENSIONS SYMBOL Millimeters Minimum N Maximum 8 A -- 1.20 A1 0.05 0.15 A2 0.80 1.05 b 0.19 0.30 c 0.09 0.20 D 2.90 E E1 3.10 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 843251BGI-12 www.icst.com/products/hiperclocks.html 11 REV. A JANUARY 10, 2006 PRELIMINARY ICS843251I-12 FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V LVPECL CLOCK GENERATOR Integrated Circuit Systems, Inc. TABLE 8. ORDERING INFORMATION Part/Order Number Marking Package Shipping Packaging Temperature ICS843251BGI-12 TBD 8 Lead TSSOP tube -40°C to 85°C ICS843251BGI-12T TBD 8 Lead TSSOP 2500 tape & reel -40°C to 85°C ICS843251BGI-12LF BI12L 8 Lead "Lead-Free" TSSOP tube -40°C to 85°C ICS843251BGI-12FT BI12L 8 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. 843251BGI-12 www.icst.com/products/hiperclocks.html 12 REV. A JANUARY 10, 2006