SM802101 ClockWorks™ PCI-e Octal 100MHz/200MHz Ultra-Low Jitter, HCSL Frequency Synthesizer General Description Features The SM802101 is a member of the ClockWorks™ family of devices from Micrel and provides an extremely low-noise timing solution for PCI-Express 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 eight HCSL output clocks at 100MHz or 200MHz. The SM802101 accepts a 25MHz crystal or LVCMOS reference clock. Data sheets and support documentation can be found on Micrel’s web site at: www.micrel.com. • Generates eight HCSL clock outputs at 100MHz or 200MHz • 2.5V or 3.3V operating range • Typical phase jitter @ 100MHz (1.875MHz to 20MHz): 105fs • Industrial temperature range (–40°C to +85°C) • Green, RoHS, and PFOS compliant • Available in 44-pin 7mm × 7mm QFN package Applications • PCI-Express 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 July 2011 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Ordering Information(1) Part Number Marking Shipping Temperature Range Package SM802101UMG 802101 Tray –40°C to +85°C 44-Pin QFN SM802101UMGR 802101 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 1, 2 /Q5, Q5 4, 5 /Q6, Q6 7, 8 /Q7, Q7 25, 26 /Q0, Q0 28, 29 /Q1, Q1 32, 33 /Q2, Q2 35, 36 /Q3, Q3 41, 42 /Q4, Q4 July 2011 Pin Type Pin Level O, (DIF) HCSL 2 Pin Function Differential Clock Output M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Pin Description (Continued) Pin Number 14 Pin Name Pin Type FSEL I, (SE) Pin Level Pin Function LVCMOS Frequency Select, 1 = 100MHz, 0 = 200MHz, 45KΩ pull-up 12, 13 VDD PWR Power Supply 31, 37, 38 VDDO1 PWR Power Supply for Outputs Q0 – Q3 16, 43, 44 VDDO2 PWR Power Supply for Outputs Q4 – Q7 21, 23 (Exposed Pad) PWR Core Power Supply Ground. The exposed pad must be connected to the VSS ground plane. VSS 24, 39 VSSO1 PWR Power Supply Ground for Q0 – Q3 3, 6, 40 VSSO2 PWR Power Supply Ground for Outputs Q4 – Q7 PLL Bypass, Selects Output Source 9 PLL_BYPASS I, (SE) LVCMOS 0 = Normal PLL Operation 1 = Output from Input Reference Clock or Crystal 45KΩ pull-down I, (SE) LVCMOS Selects PLL Input Reference Source 10 XTAL_SEL 11, 20, 27, 30, 34 TEST 17 REF_IN I, (SE) LVCMOS 18 XTAL_IN I, (SE) 12pF crystal Crystal Reference Input, no load caps needed (see Figure 5). 19 XTAL_OUT O, (SE) 12pF crystal Crystal Reference Output, no load caps needed (see Figure 5). 15 OE1 I, (SE) LVCMOS 22 OE2 I, (SE) LVCMOS PLL_BYPASS XTAL_SEL OE2 OE1 INPUT OUTPUT 0 − 1 1 − PLL 1 − 1 1 − XTAL/REF_IN − 0 1 1 REF_IN − − 1 1 1 XTAL − − − − 1 0 − − 0 1 Q4-Q7 Tri-state Q0-Q3 Tri-state 0 = REF_IN, 1 = XTAL, 45KΩ pull-up Factory Test pins, Do not connect anything to these pins. Reference Clock Input Output Enable, Outputs Q0 – Q3 disable to tri-state, 0 = Disabled, 1 = Enabled, 45KΩ pull-up Output Enable, Outputs Q4 – Q7 disable to tri-state, 0 = Disabled, 1 = Enabled, 45KΩ pull-up Truth Tables FSEL Output Frequency (MHz) 0 200 1 100 July 2011 3 − M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 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, 20s)............................ 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 Junction Thermal Resistance(3) QFN (θJA) Still-Air......................................................24°C/W QFN (ψJB) 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 VDD, VDDO1/2 VDD, VDDO1/2 IDD Min. Typ. Max. Units 2.5V Operating Voltage 2.375 2.5 2.625 V 3.3V Operating Voltage 3.135 3.3 3.465 V Eight Outputs enabled, 100MHz Outputs 50Ω to VSS 217 270 Eight Outputs enabled, 200MHz Outputs 50Ω to VSS 229 285 Supply current VDD + VDDO Condition mA Four Outputs enabled, 100MHz Outputs 50Ω to VSS, OE1 or OE2 = 0 149 185 Four Outputs enabled, 200MHz Outputs 50Ω to VSS, OE1 or OE2 =0 158 197 Min Typ. Max. Units HCSL 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 VSS Symbol Parameter Condition VOH Output High Voltage 660 700 850 mV VOL Output Low Voltage −150 0 27 mV VCROSS Crossing Point Voltage 250 350 550 mV 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(s) after thermal equilibrium has been established. July 2011 4 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 LVCMOS (PLL_BYPASS, XTAL_SEL, FSEL, OE1, OE2) DC Electrical Characteristics(4) VDD = 3.3V ±5%, or 2.5V ±5%, TA = −40°C to +85°C. Symbol Parameter Condition 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 Min. Typ. Max. Units 2 VDD + 0.3 V −0.3 0.8 V 150 μA −150 μA 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 XTAL_SEL = VIH, VIN = VDD Typ. 20 μA Crystal Characteristics Parameter Condition Mode of Oscillation Frequency Equivalent Series Resistance (ESR) Shunt Capacitor, C0 Correlation Drive Level 12pF Load July 2011 Min. Typ. Max. Units Fundamental, Parallel Resonant 25 1 10 5 50 5 100 MHz Ω pF uW M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 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 VSS Symbol Parameter Condition Min. Typ. Max. Units FOUT1 Output Frequency FSEL=1 100 MHz FOUT2 Output Frequency FSEL=0 200 MHz FREF Reference Input Frequency 25 MHz TR/TF LVPECL Output Rise/Fall Time ODC Output Duty Cycle TSKEW Output-to-Output Skew TLOCK PLL Lock Time 20% – 80% RMS Phase Jitter 300 450 ps 48 50 52 % Note 6 100MHz Integration Range (1.875MHz – 20MHz) Integration Range (12kHz – 20MHz) Tjit(∅) 150 ps 20 ms 105 250 (7) Spurious Noise Components 45 fs 200MHz Integration Range (1.875MHz – 20MHz) Integration Range (12kHz – 20MHz) 100 250 25MHz using 100MHz 25MHz using 200MHz -85 -90 dBc Notes: 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; Measured at the output differential crossing points. 7. Measured using 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. July 2011 6 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Application Information Input Reference When operating with a crystal input reference, do not apply a switching signal to REF_IN. HCSL Outputs HCSL outputs are to be terminated with 50Ω to VSS. For best performance load all outputs. If you want to ACcouple or change the termination, contact Micrel’s application group at: [email protected]. 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]. July 2011 7 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Phase Noise Plots Phase Noise Plot: 100MHz, 1.875MHz − 20MHz 101fS Phase Noise Plot: 100MHz, 12kHz − 20MHz 254fS July 2011 8 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Phase Noise Plots (Continued) Phase Noise Plot: 200MHz, 1.875MHz − 20MHz 94fS Phase Noise Plot: 200MHz, 12kHz − 20MHz 253fS July 2011 9 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Figure 1. Duty Cycle Timing Figure 2. All Outputs Rise/Fall Time Figure 3. RMS Phase/Noise Jitter July 2011 10 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Figure 4. HCSL Output Load and Test Circuit Figure 5. Crystal Input Interface July 2011 11 M9999-072111-A [email protected] or (408) 955-1690 Micrel, Inc. SM802101 Package Information 44-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. July 2011 12 M9999-072111-A [email protected] or (408) 955-1690