SM802128 ClockWorksΤΜ 10GbE Octal 156.25MHz, 312.5MHz, Ultra-Low Jitter, LVPECL Frequency Synthesizer General Description Features • Generates eight LVPECL clocks at 156.25MHz or The SM802128 is a member of the ClockWorks™ family of 312.5MHz devices from Micrel and provides an extremely low-noise timing solution for 10GbE Ethernet clock signals. It is • 2.5V or 3.3V operating range based upon a unique patented RotaryWave® architecture • Typical phase jitter @ 156.25MHz that provides very low phase noise. (1.875MHz to 20MHz): 110fs with crystal reference The device operates from a 3.3V or 2.5V power supply • Industrial temperature range (–40°C to +85°C) and synthesizes eight LVPECL output clocks at • Green, RoHS, and PFOS compliant 156.25MHz or 312.5MHz. The SM802128 accepts a 25 MHz crystal or LVCMOS reference clock. • Available in 44-pin 7mm × 7mm QFN package Data sheet and support documentation can be found on Micrel’s web site at: www.micrel.com. ________________________________________________________________________________________________________ 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 2012 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Ordering Information (1) Marking Shipping Temperature Range Package SM802128UMG Part Number 802128 Tray –40°C to +85°C 44-Pin QFN SM802128UMGTR 802128 Tape and Reel –40°C to +85°C 44-Pin QFN Note: 1. Devices are Green, RoHS, and PFOS compliant. Pin Configuration 44-Pin QFN (Top View) Pin Description Pin Number Pin Name 25, 26 /Q1, Q1 28, 29 /Q2, Q2 32, 33 /Q3, Q3 35, 36 /Q4, Q4 41, 42 /Q5, Q5 1, 2 /Q6, Q6 4, 5 /Q7, Q7 Pin Type Pin Level Pin Function O, (DIF) LVPECL Differential Clock Outputs from Bank 1 (156.25MHz or 312.5MHz). O, (DIF) LVPECL Differential Clock Outputs from Bank 2 (156.25MHz or 312.5MHz). 7, 8 /Q8, Q8 31, 37, 38 VDDO1 PWR Power Supply for the Outputs on Bank 1. 43, 44, 16 VDDO2 PWR Power Supply for the Outputs on Bank 2. 24, 39 VSSO1 PWR Power Supply Ground for the Outputs on Bank 1. January 2012 2 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Pin Description (continued) Pin Number Pin Name Pin Type 3, 6, 40 VSSO2 PWR 11, 20, 27, 30, 34 TEST 12, 13 VDD Pin Level Pin Function Power Supply Ground for the Outputs on Bank 2 Factory Test Pins. Do not connect anything to these pins. PWR Core Power Supply Core Power Supply Ground. The exposed pad must be connected to the VSS ground plane. VSS 21, 23 (Exposed Pad) PWR 17 REF_IN I, (SE) LVCMOS 18 XTAL_IN I, (SE) Crystal 19 XTAL_OUT O, (SE) Crystal 15 OE1 I, (SE) LVCMOS 22 OE2 I, (SE) LVCMOS 9 PLL_BYPASS I, (SE) LVCMOS Reference Clock Input Crystal Reference Input, no load caps needed (See Figure 5). Crystal Reference Output, no load caps needed (See Figure 5). Output Enable, Q1-Q4 disables to tri-state, 0 = Disabled, 1 = Enabled, 45KΩ Pull-Up. Output Enable, Q5-Q8 disables to tri-state, 0 = Disabled, 1 = Enabled, 45KΩ Pull-Up. PLL Bypass, Selects Output Source 0 = Normal PLL Operation 1 = Output from Input Reference Clock or Crystal 45KΩ Pull-Down 10 XTAL_SEL I, (SE) LVCMOS 14 FSEL I, (SE) LVCMOS Selects PLL Input Reference Source 0 = REF_IN, 1 = XTAL, 45KΩ Pull-Up Frequency Select, 1 = 156.25MHz, 0 = 312.5MHz, 45KΩ Pull-Up Truth Tables OE1/2 0 Tri-state 1 LVPECL FSEL Output Frequency (MHz) 0 312.5 1 156.25 PLL_BYPASS/CSB XTAL_SEL 0 − − PLL 1 − − XTAL/REF_IN − 0 REF_IN − − 1 XTAL − January 2012 3 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Absolute Maximum Ratings (1) Operating Ratings (2) Supply Voltage (VDD, VDDO1/2) ……....................+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 Supply Voltage (VDD, VDDO1/2) ............... +2.375V to +3.465V Ambient Temperature (TA) .......................... –40°C to +85°C (3) Junction Thermal Resistance QFN (θ JA) Still-Air ............................................................... 24°C/W QFN (ψ JB) Junction-to-Board ................................................ 8°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 Parameter Condition Min. Typ. Max. Units VDD, VDDO1/2 2.5V Operating Voltage VDDO1=VDDO2 2.375 2.5 2.625 V VDD, VDDO1/2 3.3V Operating Voltage VDDO1=VDDO2 3.135 3.3 3.465 V IDD Supply current VDD + VDDO Outputs open 156.25MHz 220 275 312.5MHz 275 345 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 Parameter Min. Typ. Max. Units VOH Output High Voltage Condition VDDO – 1.145 VDDO – 0.97 VDDO – 0.845 V VOL Output Low Voltage VDDO – 1.945 VDDO – 1.77 VDDO – 1.645 V VSWING Output Voltage Swing 0.6 0.8 1.0 V LVCMOS (PLL_BYPASS, XTAL_SEL, OE1, OE2, FSEL) DC Electrical Characteristics (4) VDD = 3.3V ±5%, or 2.5V ±5%, TA = −40°C to +85°C. Symbol Parameter VIH Input High Voltage VIL Input Low Voltage IIH Input High Current VDD = VIN = 3.465V IIL Input Low Current VDD = 3.465V, VIN = 0V January 2012 Condition Min. Max. Units 2 VDD + 0.3 V −0.3 0.8 V 150 μA −150 4 Typ. μA [email protected] or (408) 955-1690 Micrel, Inc. SM802128 REF_IN DC Electrical Characteristics(4) VDD = 3.3V ±5%, or 2.5V ±5%, TA = -40°C to +85°C. Symbol Parameter VIH Input High Voltage VIL Input Low Voltage IIN Input Current Condition Min. XTAL_SEL = VIL, VIN = 0V to VDD Max. Units 1.1 VDD + 0.3 V −0.3 0.6 V −5 5 μA XTAL_SEL = VIH, VIN = VDD Typ. 20 µA Crystal Characteristics Parameter Condition Mode of Oscillation Frequency 10pF Load Min. Equivalent Series Resistance (ESR) Shunt Capacitor, C0 Correlation Drive Level January 2012 Typ. Max. Fundamental, Parallel Resonant 25 1 10 5 50 5 100 Units MHz Ω pF uW [email protected] or (408) 955-1690 Micrel, Inc. SM802128 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 Parameter Condition FOUT1 Output Frequency 1 FSEL = 1 156.25 MHz FOUT2 Output Frequency 2 FSEL = 0 312.5 MHz FREF Reference Input Frequency TR/TF ODC LVPECL Output Rise/Fall Time Output Duty Cycle TSKEW Output-to-Output Skew TLOCK PLL Lock Time Min Max Units 25 20% – 80% Q1 – Q8 MHz 80 175 350 ps 48 50 52 45 % ps 20 ms (6) 156.25MHz Integration Range (1.875MHz – 20MHz) Integration Range (12kHz – 20MHz) Tjit(∅) Typ 110 250 RMS Phase Jitter(7) Spurious Noise Components fs 312.5MHz Integration Range (1.875MHz – 20MHz) Integration Range (12kHz – 20MHz) 110 250 6.25MHz using 156.25MHz 12.5MHz using 312.5MHz -80 -85 dBc Notes: 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. 2. The data sheet limits are not guaranteed if the device is operated beyond the operating ratings. 3. Package thermal resistance assumes exposed pad is soldered (or equivalent) to the devices most negative potential on the PCB. 4. The circuit is designed to meet the AC and DC specifications shown in the above table after thermal equilibrium has been established. 5. All phase−noise measurements were taken with an Agilent 5052B phase−noise system. 6. 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. 7. Measured using a 25MHz crystal as the input reference source. If using an external reference input, use a low phase noise source. With an external reference, the phase noise will follow the input source phase noise up to about 1MHz offset frequency. January 2012 6 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 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 and do not place switching signals or noisy supplies under the crystal. Crystal load capacitance is built inside the die so no external capacitance is needed. See the Selecting a quartz crystal for the Clockworks Flex I Family of Precision Synthesizers application note for further details. Contact Micrel’s HBW applications group if you need assistance on selecting a suitable crystal for your application at: [email protected]. January 2012 7 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Phase Noise Plots Phase Noise Plot: 156.25MHz, 1.875MHz − 20MHz 108fs Phase Noise Plot: 156.25MHz, 12kHz − 20MHz 244fs January 2012 8 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Phase Noise Plots (Continued) Phase Noise Plot: 312.5MHz, 1.875MHz − 20MHz 113fs Phase Noise Plot: 312.5MHz, 12kHz − 20MHz 248fs January 2012 9 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Figure 1. Duty Cycle Timing Figure 2. All Outputs Rise/Fall Time Figure 3. RMS Phase/Noise/Jitter January 2012 10 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Figure 4. LVPECL Output Load January 2012 Figure 5. Crystal Input Interface 11 [email protected] or (408) 955-1690 Micrel, Inc. SM802128 Package Information 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. © 2012 Micrel, Incorporated. January 2012 12 [email protected] or (408) 955-1690