ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR GENERAL DESCRIPTION FEATURES The ICS843011 is a Fibre Channel Clock Generator. The ICS843011 uses a 26.5625MHz crystal to synthesize 106.25MHz or a 25MHz crystal to synthesize 100MHz. The ICS843011 has excellent <1ps phase jitter performance, over the 637kHz - 10MHz integration range. The ICS843011 is packaged in a small 8-pin TSSOP, making it ideal for use in systems with limited board space. * One differential 3.3V LVPECL output * Crystal oscillator interface designed for 26.5625MHz 18pF parallel resonant crystal * Output frequency: 106.25MHz or 100MHz * VCO range: 560MHz - 680MHz * RMS phase jitter @ 100MHz, using a 25MHz crystal (637kHz - 10MHz): 0.80ps (typical) * RMS phase noise at 106.25MHz Phase noise: Offset Noise Power 100Hz ............... -92.8 dBc/Hz 1kHz ............. -119.6 dBc/Hz 10kHz ............. -129.5 dBc/Hz 100kHz ............. -130.5 dBc/Hz * 3.3V operating supply * Available in both standard (RoHS 5) and lead-free (RoHS 6) packages * -40C to 85C ambient operating temperature FREQUENCY TABLE Crystal (MHz) Output Frequency (MHz) 26.5625 106.25 25 100 BLOCK DIAGRAM XTAL_IN OSC XTAL_OUT PIN ASSIGNMENT Phase Detector VCO 637.5MHz w/ 26.5625MHz Ref. /6 Q0 VCCA VEE XTAL_OUT XTAL_IN 1 2 3 4 8 7 6 5 VCC Q0 nQ0 nc ICS843011 M = /24 (fixed) 843011AG nQ0 8-Lead TSSOP 4.40mm x 3.0mm x 0.925mm package body G Package Top View www.idt.com 1 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR TABLE 1. PIN DESCRIPTIONS Number Name Type 1 VCCA Power Analog supply pin. 2 3, 4 5 VEE XTAL_OUT, XTAL_IN nc Power Unused Negative supply pin. Crystal oscillator interface. XTAL_IN is the input, XTAL_OUT is the output. No connect. 6, 7 nQ0, Q0 Output Differential clock outputs. LVPECL interface levels. 8 VCC Power Core supply pin. Input Description TABLE 2. PIN CHARACTERISTICS Symbol Parameter CIN Input Capacitance 843011AG Test Conditions Minimum Typical 4 www.idt.com 2 Maximum Units pF REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC 4.6V Inputs, VI -0.5V to VCC + 0.5V Outputs, IO Continuous Current Surge Current 50mA 100mA Package Thermal Impedance, JA 101.7C/W (0 mps) Storage Temperature, TSTG -65C to 150C 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 = 3.3V5%, TA = -40C TO 85C Symbol Parameter VCC Core Supply Voltage VCCA Analog Supply Voltage ICCA Analog Supply Current IEE Power Supply Current Test Conditions Minimum Typical Maximum Units 3.135 3.3 3.465 V 3.135 3.3 3.465 V 12 mA 93 mA Maximum Units included in IEE TABLE 3B. LVPECL DC CHARACTERISTICS, VCC = 3.3V5%, TA = -40C TO 85C Symbol Parameter Test Conditions Minimum Typical VOH Output High Voltage; NOTE 1 VCC - 1.4 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 50 to VCC - 2V. TABLE 4. CRYSTAL CHARACTERISTICS Parameter Test Conditions Minimum Mode of Oscillation Typical Fundamental Frequency 26.5625 MHz Equivalent Series Resistance (ESR) 25 50 Shunt Capacitance 7 pF TABLE 5. AC CHARACTERISTICS, VCC = 3.3V5%, TA = -40C TO 85C Symbol Parameter FOUT tjit(O) Test Conditions Output Frequency RMS Phase Jitter (Random); NOTE 1 tR / tF Output Rise/Fall Time odc Output Duty Cycle Minimum Typical 93.33 106.25MHz; Integration Range: 637KHz - 10MHz 100MHz; Integration Range: 637KHz - 10MHz 20% to 80% Maximum Units 113.33 MHz 0.80 ps 0.80 ps 300 600 ps 48 52 % NOTE 1: Please refer to the Phase Noise Plot. 843011AG www.idt.com 3 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR TYPICAL PHASE NOISE AT 100MHZ 0 -10 Filter -20 -30 -40 100MHz -50 RMS Phase Noise Jitter 637K to 10MHz = 0.80ps (typical) -70 -80 -90 Raw Phase Noise Data -100 -110 NOISE POWER dBc Hz -60 -120 -130 -140 -150 -160 -170 Phase Noise Result by adding a Filter to raw data -180 -190 100 1k 10k 100k 1M 10M 100M OFFSET FREQUENCY (HZ) TYPICAL PHASE NOISE AT 106.25MHZ 0 -10 -20 Fibre Channel Filter -30 -40 106.25MHz -50 RMS Phase Noise Jitter 637K to 10MHz = 0.80ps (typical) -70 -80 -90 Raw Phase Noise Data -100 -110 NOISE POWER dBc Hz -60 -120 -130 -140 -150 -160 -170 Phase Noise Result by adding Fibre Channel Filter to raw data -180 -190 100 1k 10k 100k 1M 10M 100M OFFSET FREQUENCY (HZ) 843011AG www.idt.com 4 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR PARAMETER MEASUREMENT INFORMATION 2V Phase Noise Plot Qx SCOPE Noise Power V CC LVPECL Phase Noise Mask nQx VEE f1 -1.3V 0.165V Offset Frequency f2 RMS Jitter = Area Under the Masked Phase Noise Plot 3.3V OUTPUT LOAD AC TEST CIRCUIT RMS PHASE JITTER nQ0 80% Q0 80% VSW I N G Pulse Width t odc = Clock Outputs PERIOD t PW 20% 20% tR tF t PERIOD OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD 843011AG OUTPUT RISE/FALL TIME www.idt.com 5 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR APPLICATION INFORMATION POWER SUPPLY FILTERING TECHNIQUES As in any high speed analog circuitry, the power supply pins are vulnerable to random noise. The ICS843011 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 10 resistor along with a 10F and a .01F bypass capacitor should be connected to each VCCA pin. 3.3V VCC .01F 10 V CCA .01F 10F FIGURE 1. POWER SUPPLY FILTERING CRYSTAL INPUT INTERFACE allel 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 ICS843011 has been characterized with 18pF parallel resonant crystals. The capacitor values, C1 and C2, shown in Figure 2 below were determined using a 26.5625MHz, 18pF par- XTAL_OUT C1 33p X1 18pF Parallel Crystal XTAL_IN C2 22p Figure 2. CRYSTAL INPUt INTERFACE 843011AG www.idt.com 6 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR APPLICATION SCHEMATIC Figure 3A shows a schematic example of the ICS843011. An example of LVEPCL termination is shown in this schematic. Additional LVPECL termination approaches are shown in the LVPECL Termination Application Note. In this example, an 18 pF parallel resonant 26.5625MHz crystal is VCC used for generating 106.25MHz output frequency. The C1 = 27pF and C2 = 33pF are recommended for frequency accuracy. For different board layout, the C1 and C2 values may be slightly adjusted for optimizing frequency accuracy. VCCA VCC R2 10 C3 10uF C4 0.01u R3 133 U1 R5 133 Zo = 50 Ohm Q 1 2 3 4 F p 8 1 C2 33pF VCCA VEE XTAL_OUT XTAL_IN VCC Q0 nQ0 NC 8 7 6 5 VCC + Zo = 50 Ohm nQ X1 - ICS843011 R4 82.5 C5 0.1u C1 22pF R6 82.5 VCC=3.3V FIGURE 3A. ICS843011 SCHEMATIC EXAMPLE PC BOARD LAYOUT EXAMPLE Figure 3B shows an example of ICS843011 P.C. board layout. The crystal X1 footprint shown in this example allows installation of either surface mount HC49S or throughhole HC49 package. The footprints of other components in this example are listed in the Table 6. There should be at least one decoupling capacitor per power pin. The decoupling capacitors should be located as close as possible to the power pins. The layout assumes that the board has clean analog power ground plane. TABLE 6. FOOTPRINT TABLE Reference Size C1, C2 0402 C3 0805 C4, C5 0603 R2 0603 NOTE: Table 6, lists component sizes shown in this layout example. FIGURE 3B. ICS843011 PC BOARD LAYOUT EXAMPLE 843011AG www.idt.com 7 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR POWER CONSIDERATIONS This section provides information on power dissipation and junction temperature for the ICS843011. Equations and example calculations are also provided. 1. Power Dissipation. The total power dissipation for the ICS843011 is the sum of the core power plus the power dissipated in the load(s). The following is the power dissipation for VCC = 3.3V + 5% = 3.465V, which gives worst case results. NOTE: Please refer to Section 3 for details on calculating power dissipated in the load. * * Power (core)MAX = VCC_MAX * IEE_MAX = 3.465V * 93mA = 322.2mW Power (outputs)MAX = 30mW/Loaded Output pair Total Power_MAX (3.465V, with all outputs switching) = 322.2mW + 30mW = 352.2mW 2. Junction Temperature. Junction temperature, Tj, is the temperature at the junction of the bond wire and bond pad and directly affects the reliability of the device. The maximum recommended junction temperature for the devices is 125C. The equation for Tj is as follows: Tj = JA * Pd_total + TA Tj = Junction Temperature JA = Junction-to-Ambient Thermal Resistance Pd_total = Total Device Power Dissipation (example calculation is in section 1 above) TA = Ambient Temperature In order to calculate junction temperature, the appropriate junction-to-ambient thermal resistance JA must be used. Assuming a moderate air flow of 1 meter per second and a multi-layer board, the appropriate value is 90.5C/W per Table 6 below. Therefore, Tj for an ambient temperature of 85C with all outputs switching is: 85C + 0.352W * 90.5C/W = 116.9C. This is below the limit of 125C. This calculation is only an example. Tj will obviously vary depending on the number of loaded outputs, supply voltage, air flow, and the type of board (single layer or multi-layer). TABLE 6. THERMAL RESISTANCE JA FOR 8-PIN TSSOP, FORCED CONVECTION JA by Velocity (Meters per Second) Multi-Layer PCB, JEDEC Standard Test Boards 843011AG 0 1 2.5 101.7C/W 90.5C/W 89.8C/W www.idt.com 8 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR 3. Calculations and Equations. The purpose of this section is to derive the power dissipated into the load. LVPECL output driver circuit and termination are shown in Figure 4. VCC Q1 VOUT RL 50 VCC - 2V FIGURE 4. LVPECL DRIVER CIRCUIT AND TERMINATION To calculate worst case power dissipation into the load, use the following equations which assume a 50 load, and a termination voltage of V - 2V. CC * For logic high, VOUT = V OH_MAX (V CCO_MAX * -V OH_MAX OL_MAX CCO_MAX -V CC_MAX - 0.9V ) = 0.9V For logic low, VOUT = V (V =V =V CC_MAX - 1.7V ) = 1.7V OL_MAX Pd_H is power dissipation when the output drives high. Pd_L is the power dissipation when the output drives low. Pd_H = [(V OH_MAX - (V CC_MAX - 2V))/R ] * (V CC_MAX L -V OH_MAX ) = [(2V - (V CC_MAX -V OH_MAX ))/R ] * (V CC_MAX L -V OH_MAX )= [(2V - 0.9V)/50] * 0.9V = 19.8mW Pd_L = [(V OL_MAX - (V CC_MAX - 2V))/R ] * (V L CC_MAX -V OL_MAX ) = [(2V - (V CC_MAX -V OL_MAX ))/R ] * (V L CC_MAX -V OL_MAX )= [(2V - 1.7V)/50] * 1.7V = 10.2mW Total Power Dissipation per output pair = Pd_H + Pd_L = 30mW 843011AG www.idt.com 9 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR RELIABILITY INFORMATION TABLE 7. JAVS. AIR FLOW TABLE FOR 8 LEAD TSSOP JA by Velocity (Meters per Second) Multi-Layer PCB, JEDEC Standard Test Boards 0 1 2.5 101.7C/W 90.5C/W 89.8C/W TRANSISTOR COUNT The transistor count for ICS843011 is: 2436 843011AG www.idt.com 10 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR PACKAGE OUTLINE - G SUFFIX FOR 8 LEAD TSSOP TABLE 8. PACKAGE DIMENSIONS SYMBOL Millimeters Minimum N A Maximum 8 -- 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 3.10 E E1 6.40 BASIC 4.30 e 4.50 0.65 BASIC L 0.45 0.75 0 8 aaa -- 0.10 Reference Document: JEDEC Publication 95, MO-153 843011AG www.idt.com 11 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR TABLE 9. ORDERING INFORMATION Part/Order Number Marking Package Shipping Package Temperature 843011AG 3011A 8 lead TSSOP tube -40C to 85C 843011AGT 3011A 8 lead TSSOP 2500 tape & reel -40C to 85C 843011AGLF 011AL 8 lead "Lead-Free" TSSOP tube -40C to 85C 843011AGLFT 011AL 8 lead "Lead-Free" TSSOP 2500 tape & reel -40C to 85C NOTE: Par ts that are ordered with an "LF" suffix to the par t number are the Pb-Free configuration and are RoHS compliant. While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology, Inc. (IDT) 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 IDT. IDT reserves the right to change any circuitry or specifications without notice. IDT does not authorize or warrant any IDT product for use in life support devices or critical medical instruments. 843011AG www.idt.com 12 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR Rev B B Table 3A T9 Page 3 12 B T9 12 1 B B B 843011AG 6 7 T9 12 T9 12 14 REVISION HISTORY SHEET Description of Change Power Supply DC Characteristics Table - added ICCA spec. Ordering Information Table - corrected count from 154 to 100. Ordering Information Table - corrected Lead-Free marking from 3011AL to 011AL. Changed ambient operating temperature bullet from -30C to 85C to -40C to 85C and throughout data sheet. Cr ystal Input Interface - changed capacitor C2 value from 27p to 22p. Application Schematic - corrected schematic to reflect Cr ystal Input Interface change. Ordering Information Table - deleted tube count in Shipping Packaging column. Updated datasheet's header/footer with IDT from ICS. Removed ICS prefix from Par t/Order Number column. Added Contact Page. www.idt.com 13 Date 8/23/04 10/13/04 10/20/04 12/10/04 1/26/07 7/26/10 REV. B JULY 26, 2010 ICS843011 FEMTOCLOCKSTM CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR We've Got Your Timing Solution. 6024 Silver Creek Valley Road San Jose, CA 95138 Sales Tech Support 800-345-7015 (inside USA) +408-284-8200 (outside USA) Fax: 408-284-2775 netcom@idt.com (c) 2010 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. IDT, the IDT logo, ICS and HiPerClockS are trademarks of Integrated Device Technology, Inc. Accelerated Thinking is a service mark of Integrated Device Technology, Inc. All other brands, product names and marks are or may be trademarks or registered trademarks used to identify products or services of their respective owners. Printed in USA 843011AG www.idt.com 14 REV. B JULY 26, 2010