SM802108UMGR

SM802108 ClockWorks™ 10GbE & GbE (156.25MHz, 125MHz) Ultra-Low Jitter, LVPECL Frequency Synthesizer General Description The SM802108 is a member of the ClockWorks™ family of devices from Micrel and provides an extremely low-noise timing solution for GbE and 10GbE Ethernet clock signals. It is based upon a unique patented RotaryWave® architecture that provides very low phase noise. The device operates from a 3.3V or 2.5V power supply and synthesizes two LVPECL output clocks at 156.25MHz and another two at 125MHz. The SM802108 accepts a 25 MHz crystal or LVCMOS reference clock. Data sheets and support documentation can be found on Micrel’s web site at: www.micrel.com. Features • Generates two LVPECL clock outputs at 156.25MHz and two LVPECL clock outputs at 125MHz • 2.5V or 3.3V operating range • Typical phase jitter @ 156.25MHz (1.875MHz to 20MHz): 110fs (typical) at 3.3V • Industrial temperature range • Green, RoHS, and PFOS compliant • Available in 24-pin 4mm × 4mm QFN package Applications • 10Gigabit Ethernet • Gigabit Ethernet ___________________________________________________________________________________________________________ Block Diagram ClockWorks is a trademark of Micrel, Inc RotaryWave is a registered trademark of Multigig, Inc. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com January 2011 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Ordering Information Part Number SM802108UMG SM802108UMGR Note: 1. Devices are Green, RoHS, and PFOS compliant. Marking 802108 802108 Shipping Tube Tape and Reel Junction Temperature Range –40°C to +85°C –40°C to +85°C Package 24-Pin QFN 24-Pin QFN Pin Configuration 24-Pin QFN (Top View) Pin Description Pin Number 16, 17 20, 21 23, 24 3, 4 1 2 Pin Name /Q0, Q0 /Q1, Q1 /Q2, Q2 /Q3, Q3 VDDO2 VSSO2 Pin Type O, (DIF) O, (DIF) PWR PWR Pin Level LVPECL LVPECL Pin Function Differential Clock Outputs from Bank 1 156.25MHz Differential Clock Outputs from Bank 2 125MHz Power Supply for Output Bank 2 Power Supply Ground for Output Bank 2 PLL Bypass, Selects Output Source 5 PLL_BYPASS I, (SE) LVCMOS 0 = Normal PLL Operation 1 = Output from Input Reference Clock or Crystal 45KΩ pull-down 6 XTAL_SEL I, (SE) LVCMOS Selects PLL Input Reference Source 0 = REF_IN, 1 = XTAL, 45KΩ pull-up January 2011 2 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Pin Description (Continued) Pin Number 7, 12, 15, 19 8 9 10 11 13, 14 18 22 Pin Name TEST VDD REF_IN XIN XOUT VSS VDDO1 VSSO1 PWR I, (SE) I, (SE) O, (SE) PWR PWR PWR LVCMOS 12pF crystal 12pF crystal Pin Type Pin Level Pin Function Factory Test Pins, Do not connect anything to these pins. Core Power Supply Reference Clock Input Crystal Reference Input, no load caps needed. See Fig. 5. Crystal Reference Output, no load caps needed. See Fig. 5. Core Power Supply Ground Power Supply for Output Bank 1 Power Supply Ground for Output Bank 1 Application Information Input Reference When operating with a crystal input reference, do not apply a switching signal to REF_IN. Crystal Layout Keep the layers under the crystal as open as possible. Do not place switching signals or noisy supplies under the crystal. Truth Table PLL_BYPASS 0 1 − − XTAL_SEL − − 0 1 INPUT − − REF_IN XTAL OUTPUT PLL XTAL/REF_IN − − January 2011 3 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Absolute Maximum Ratings(1) Supply Voltage (VDD, VDDOx) ........................................+4.6V Input Voltage (VIN). ............................. –0.50V to VDD + 0.5V Lead Temperature (soldering, 20sec.)....................... 260°C Case Temperature ..................................................... 115°C Storage Temperature (Ts) .........................–65°C to +150°C Operating Ratings(2) Supply Voltage (VDD, VDDOx) ................. +2.375V to +3.465V Ambient Temperature (TA) .......................... –40°C to +85°C Junction Thermal Resistance(3) QFN (θJA) Still-Air.........................................................50°C/W QFN (ψJB) Junction-to-Board .......................................30°C/W DC Electrical Characteristics(4) VDD = VDDO1/2 = 3.3V ±5% or 2.5V ±5% VDD = 3.3V ±5%, VDDO1/2 = 3.3V ±5% or 2.5V ±5% TA = −40°C to +85°C. Symbol VDD, VDDOx VDD, VDDOx IDD IDD Parameter 2.5V Operating Voltage 3.3V Operating Voltage Supply current VDD + VDDO Supply current VDD + VDDO Outputs open; REF_IN source, XTAL_SEL = 0 Outputs open; CRYSTAL source, XTAL_SEL = 1 Condition Min. 2.375 3.135 Typ. 2.5 3.3 130 145 Max. 2.625 3.465 165 185 Units V V mA mA LVPECL DC Electrical Characteristics(4) VDD = VDDO1/2 = 3.3V ±5% or 2.5V ±5% VDD = 3.3V ±5%, VDDO1/2 = 3.3V ±5% or 2.5V ±5% TA = −40°C to +85°C. RL = 50Ω to VDDO − 2V Symbol VOH VOL VSWING Note: 1. Permanent device damage may occur if absolute maximum ratings are exceeded. This is a stress rating only and functional operation is not implied at conditions other than those detailed in the operational sections of this data sheet. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. The data sheet limits are not guaranteed if the device is operated beyond the operating ratings. Package thermal resistance assumes exposed pad is soldered (or equivalent) to the devices most negative potential on the PCB. The circuit is designed to meet the AC and DC specifications shown in the above table(s) after thermal equilibrium has been established. Parameter Output High Voltage Output Low Voltage Output Voltage Swing Condition Min. VDDO – 1.145 VDDO – 1.945 0.6 Typ. VDDO – 0.97 VDDO – 1.77 0.8 Max. VDDO – 0.845 VDDO – 1.645 1.0 Units V V V 2. 3. 4. January 2011 4 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 LVCMOS (PLL_BYPASS, XTAL_SEL) DC Electrical Characteristics(4) VDD = 3.3V ±5%, or 2.5V ±5%, TA = −40°C to +85°C. Symbol VIH VIN IIH IIL Parameter Input High Voltage Input Low Voltage Input High Current Input Low Current VDD = VIN = 3.465V VDD = 3.465V, VIN = 0V −5 Condition Min. 2 −0.3 Typ. Max. VDD + 0.3 0.8 150 Units V V μA μA REF_IN DC Electrical Characteristics(4) VDD = 3.3V ±5%, or 2.5V ±5%, TA = −40°C to +85°C. Symbol VIH VIL IIN IIN Parameter Input High Voltage Input Low Voltage Input Current Input Current XTAL_SEL = VIL, VIN = 0V to VDD XTAL_SEL = VIH, VIN = VDD Condition Min. 1.1 −0.3 −5 20 Typ. Max. VDD + 0.3 0.6 5 Units V V μA µA Crystal Characteristics NDK NX2520SA Parameter Mode of Oscillation Frequency Equivalent Series Resistance (ESR) Shunt Capacitor, C0 Correlation Drive Level Condition 12pF Load Min. Typ. Max. Units MHz Ω pF uW Fundamental, Parallel Resonant 25 50 3 7 100 300 January 2011 5 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 AC Electrical Characteristics(4, 5) VDD = VDDO1/2 = 3.3V ±5% or 2.5V ±5% VDD = 3.3V ±5%, VDDO1/2 = 3.3V ±5% or 2.5V ±5% TA = −40°C to +85°C. RL = 50Ω to VDDO − 2V Symbol FOUT1 FOUT2 Ppm FREF TR/TF ODC TSKEW TLOCK Parameter Output Frequency 1 Output Frequency 2 Output ppm Variation Reference Input Frequency LVPECL Output Rise/Fall Time Output Duty Cycle Output-to-Output Skew PLL Lock Time 156.25MHz Integration Range (1.875MHz – 20MHz) Integration Range (12kHz – 20MHz) Tjit(∅) RMS Phase Jitter (8) Condition Min. Typ. 156.25 125 Max. Units MHz Crystal reference. Note 6 20% – 80% Within bank. Note 7 −50 25 80 48 175 50 50 350 52 45 20 ppm MHz ps % ps ms 110 250 fs 110 250 -73 -58 dBc 125MHz Integration Range (1.875MHz – 20MHz) Integration Range (12kHz – 20MHz) 6.25MHz 25MHz Spurious Noise Components Notes: 5. 6. 7. 8. All phase noise measurements were taken with an Agilent 5052B phase noise system. Crystal tolerance at room less than +/- 15ppm, over temp less than +/- 20ppm. Defined as skew between outputs at the same supply voltage and with equal load conditions and same frequency; Measured at the output differential crossing points. Measured using 25MHz crystal as the input reference source. January 2011 6 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Phase Noise Plots Phase Noise Plot: 156.25MHz, 1.875MHz − 20MHz 108fS Phase Noise Plot: 156.25MHz, 12kHz − 20MHz 253fS January 2011 7 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Phase Noise Plots (Continued) Phase Noise Plot: 125MHz, 1.875MHz − 20MHz 111fS Phase Noise Plot: 125MHz, 12kHz − 20MHz 257fS January 2011 8 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Figure 1. Duty Cycle TIming Figure 2. All Outputs Rise/Fall Time Figure 3. RMS Phase/Noise/Jitter January 2011 9 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Figure 4. LVPECL Output Load and Test Circuit Figure 5. Crystal Input Interface January 2011 10 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SM802108 Package Information 24-Pin QFN MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry, specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2011 Micrel, Incorporated. January 2011 11 M9999-012111-A hbwhelp@micrel.com or (408) 955-1690