Micrel, Inc. ULTRA-PRECISION 1:8 CML FANOUT BUFFER WITH INTERNAL I/O TERMINATION Precision Edge® SY58031U ® Precision Edge SY58031U FEATURES ■ Precision 1:8, 400mV CML fanout buffer ■ Guaranteed AC performance over temperature and voltage: • Clock frequency range: DC to >6GHz • <60ps tr / tf time • <270ps tpd • <20ps ouput-to-output skew ■ Low-jitter performance: • <10psPP total jitter (clock) • <1psRMS random jitter • <1psRMS cycle-to-cycle jitter ■ 50Ω source-terminated CML outputs ■ 400mV CML output swing into 50Ω load ■ Fully differential I/O ■ Accepts an input signal as low as 100mV ■ Unique, patent-pending input termination and VT pin accepts DC-coupled and AC-coupled differential inputs: (LVPECL, LVDS, and CML) ■ Power supply 2.5V ±5% or 3.3V ±10% ■ Industrial temperature range: –40°C to +85°C ■ Available in 32-pin (5mm × 5mm) MLF® package Precision Edge® DESCRIPTION The SY58031U is a 2.5V/3.3V precision, high-speed, fully differential CML 1:8 fanout buffer. The SY58031U is optimized to provide eight identical output copies with less than 20ps of skew and less than 10psPP total jitter. It can process clock signals as fast as 6GHz. The differential input includes Micrel’s unique, 3-pin input termination architecture that allows the SY58031U to directly interface to CML, LVPECL, and LVDS differential signals (AC- or DC-coupled) without any level-shifting or termination resistor networks in the signal path. The result is a clean, stub-free, low-jitter interface solution. The CML outputs feature 400mV typical swing into 50Ω loads and provide an extremely fast rise/fall time guaranteed to be less than 60ps. The SY58031U operates from a 2.5V ±5% supply or 3.3V ±10% supply and is guaranteed over the full industrial temperature range (–40°C to +85°C). For applications that require high-speed 1:8 LVPECL fanout buffers, consider the SY58032U and SY58033U. The SY58031U is part of Micrel’s high-speed, Precision Edge® product line. All support documentation can be found on Micrel’s web site at www.micrel.com. APPLICATIONS ■ ■ ■ ■ FUNCTIONAL BLOCK DIAGRAM All SONET and all GigE clock distribution All Fibre Channel clock and data distribution Network routing engine timing distribution High-end, low-skew multiprocessor synchronous clock distribution Q0 /Q0 Q1 /Q1 Q2 /Q2 IN Q3 50Ω VT /Q3 50Ω /IN Q4 /Q4 VREF-AC Q5 /Q5 Q6 /Q6 Q7 /Q7 Precision Edge is a registered trademark of Micrel, Inc. MicroLeadFrame and MLF are registered trademarks of Amkor Technology, Inc. M9999-020707 [email protected] or (408) 955-1690 Rev.: C 1 Amendment: /0 Issue Date: February 2007 Precision Edge® SY58031U Micrel, Inc PACKAGE/ORDERING INFORMATION VCC Q0 /Q0 Q1 /Q1 Q2 /Q2 VCC Ordering Information(1) 32 31 30 29 28 27 26 25 VCC GND IN VT VREF-AC /IN GND VCC 1 24 2 23 3 22 4 21 5 20 6 19 7 18 8 17 GND VCC Q3 /Q3 Q4 /Q4 VCC GND Part Number Package Type Operating Range Package Marking Lead Finish SY58031UMI MLF-32 Industiral SY58031U Sn-Pb SY58031UMITR(2) MLF-32 Industrial SY58031U Sn-Pb SY58031UMG(3) MLF-32 Industiral SY58031U with Pb-Free bar-line indicator Pb-Free NiPdAu SY58031UMGTR(2, 3) MLF-32 Industrial SY58031U with Pb-Free bar-line indicator Pb-Free NiPdAu VCC /Q7 Q7 /Q6 Q6 /Q5 Q5 VCC 9 10 11 12 13 14 15 16 32-Pin MLF® (MLF-32) Notes: 1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC electricals only. 2. Tape and Reel. 3. Pb-Free package recommended for new designs. PIN DESCRIPTION Pin Number Pin Name 3, 6 IN, /IN 4 VT Input Termination Center-Tap: Each input terminates to this pin. The VT pin provides a center-tap for each input (IN, /IN) to the termination network for maximum interface flexibility. See “Input Interface Applications” section. 2, 7, 17, 24 GND, Exposed Pad Ground. Exposed pad must be connected to a ground plane that is the same potential as the ground pin. 1, 8, 9, 16 18, 23, 25, 32 VCC Positive Power Supply: Bypass with 0.1µF0.01µF low ESR capacitors as close to the pins as possible. 31, 30, 29, 28, 27, 26, 22, 21, 20, 19, 15, 14, 13, 12, 11, 10 Q0, /Q0, Q1, /Q1, Q2, /Q2, Q3, /Q3, Q4, /Q4, Q5, /Q5, Q6, /Q6, Q7, /Q7 CML Differential Output Pairs: Differential buffered output copy of the input signal. The CML output swing is typically 400mV into 50Ω. Unused output pairs may be left floating with no impact on jitter. See “CML Output Termination” section. 5 VREF-AC M9999-020707 [email protected] or (408) 955-1690 Pin Function Differential Signal Input: Each pin of this pair internally terminates with 50Ω to the VT pin. Note that this input will default to an indeterminate state if left open. See “Input Interface Applications” section. Bias Reference Voltage: Equal to VCC–1.2V (typical), and used for AC-coupled applications. See “Input Interface Applications” section. When using VREF-AC, bypass with 0.01µF capacitor to VCC. Maximum sink/source current is 0.5mA. 2 Precision Edge® SY58031U Micrel, Inc. Absolute Maximum Ratings(1) Operating Ratings(2) Power Supply Voltage (VCC ) ...................... –0.5V to +4.0V Input Voltage (VIN) ......................................... –0.5V to VCC Current (VT) Source or sink current on VT pin ........................ ±100mA Input Current (VT) Source or sink current on IN, /IN .......................... ±50mA Current (VREF) Source or sink current on VREF-AC(3) ....................... ±1.5mA Lead Temperature Soldering, (20 sec.) .................... 260°C Storage Temperature Range (TS ) ........... –65°C to +150°C Power Supply Voltage (VCC) ................. +2.375V to +3.60V Ambient Temperature Range (TA) ............. –40°C to +85°C Package Thermal Resistance(4) MLF® (θJA) Still-Air ............................................................. 35°C/W MLF® (ψJB) Junction-to-Board ............................................ 20°C/W DC ELECTRICAL CHARACTERISTICS(5) TA= –40°C to +85°C Symbol Parameter Condition Min Typ Max Units VCC Power Supply Voltage 2.5V nominal 3.3V nominal 2.375 3.0 2.5 3.3 2.625 3.6 V V ICC Power Supply Current VCC = max. no lead. Includes current through 50Ω pull-ups. 265 330 mA VIH Input HIGH Voltage IN1, /IN1 VCC–1.2 VCC V VIL Input LOW Voltage IN1, /IN1 0 VIH–0.1 V VIN Input Voltage Swing IN1, /IN1, see Figure 1a. 0.1 1.7 V VDIFF_IN Differential Input Voltage Swing |IN0, /IN0|, |IN1, /IN1| IN1, /IN1, see Figure 1b. 0.2 RIN In-to-VT Resistance VT IN Max. In-to-VT (IN, /IN) 40 VREF-AC V 50 60 Ω 1.28 V VCC–1.3 VCC–1.2 VCC–1.1 V CML DC ELECTRICAL CHARACTERISTICS(5) VCC = 2.5V ±5% or 3.3V ±10%; RL = 100Ω across Q and /Q; TA= –40°C to +85°C, unless otherwise stated. Symbol Parameter Condition Min Typ VOH Output HIGH Voltage VOUT Output Voltage Swing see Figure 1a. 325 400 mV VDIFF_OUT Differential Voltage Swing see Figure 1b. 650 800 mV ROUT Output Source Impedance 40 50 VCC–0.020 Max Units VCC V 60 Ω 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 ratings 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. Due to the limited drive capability, use for input of the same package only. 4. Thermal performance assumes exposed pad is soldered (or equivalent) to the device’s most negative potential (GND) on the PCB. ψJB uses 4-layer θJA in still-air number unless otherwise stated. 5. The circuit is designed to meet the DC specifications shown in the above tables after thermal equilibrium has been established. M9999-020707 [email protected] or (408) 955-1690 3 Precision Edge® SY58031U Micrel, Inc AC ELECTRICAL CHARACTERISTICS(7) VCC = 2.5V ±5% or 3.3V ±10%; RL = 100Ω across each output pair or equivalent; TA = –40°C to +85°C, unless otherwise stated. Symbol Parameter Condition fMAX Maximum Operating Frequency VOUT ≥ 200mV tpd Propagation Delay tpd tempco Differential Propagation Delay Temperature Coefficient tSKEW Output-to-Output (Within Device) Note 8 Part-to-Part tJITTER tr, tf Min Clock Typ Max 6 (IN-to-Q) 120 Units GHz 230 270 35 fs/°C 20 ps Note 9 100 ps Cycle-to-Cycle Note 10 1 psRMS Total Jitter (Clock) Note 11 10 psPP Random Jitter (RJ) Note 12 1 psRMS 60 ps Clock Output Rise/Fall Time 7 ps 20% to 80%, at full output swing 20 45 Notes: 7. High frequency AC electricals are guaranteed by design and characterization. All outputs loaded, VIN ≥100mV. 8. Output-to-output skew is measured between outputs under identical transitions. 9. Part-to-part skew is defined for two parts with identical power supply voltages at the same temperature and with no skew of the edges at the respective inputs. Part-to-part skew includes variation in tpd. 10. Cycle-to-cycle jitter definition: The variation of periods between adjacent cycles, Tn–Tn–1 where T is the time between rising edges of the output signal. 11. Total jitter definition: With an ideal clock input of frequency ≤ fMAX, no more than one output edge in 1012 output edges will deviate by more than the specified peak-to-peak jitter value. 12. Random jitter is measured with a K28.7 comma detect character pattern, measured at 1.25Gbps and 2.5Gbps. SINGLE-ENDED AND DIFFERENTIAL SWINGS VDIFF_IN, VDIFF_OUT 800mV (Typ.) VIN, VOUT 400mV (Typ.) Figure 1a. Single-Ended Voltage Swing Figure 1b. Differential Voltage Swing TIMING DIAGRAM /IN VIN IN tpd tpd /Q VOUT Q M9999-020707 [email protected] or (408) 955-1690 4 Precision Edge® SY58031U Micrel, Inc. TYPICAL OPERATING CHARACTERISTICS VCC = 2.5V, GND = 0, VIN = 100mV, TA = 25°C, unless otherwise stated. 200MHz Output Output Swing (100mV/div.) Output Swing (100mV/div.) 2.5GHz Output TIME (50ps/div.) TIME (600ps/div.) Output Swing (100mV/div.) 7GHz Output 50 ∆ Output-to-Output Skew vs. Temperature 4.0 3.5 3.0 SKEW (ps) 500 450 400 350 300 250 200 150 100 Amplitude vs. Frequency ∆ AMPLITUDE (mV) TIME (20ps/div.) 2.5 2.0 1.5 1.0 0.5 VIN = 200mV 0.0 -40 -20 0 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 0 20 40 60 80 100 120 TEMPERATURE (°C) FREQUENCY (MHz) 195 PROPAGATION DELAY (ps) PROPAGATION DELAY (ps) Propagation Delay vs. Input Swing 202 200 198 196 194 192 190 188 186 184 182 180 100 200 300 400 500 600 700 800 VIN = 400mV 190 185 180 175 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (°C) INPUT SWING (mV) M9999-020707 [email protected] or (408) 955-1690 Propagation Delay vs. Temperature 5 Precision Edge® SY58031U Micrel, Inc INPUT BUFFER VCC IN 50Ω VT GND 50Ω /IN Figure 2. Simplified Differential Input Buffer INPUT INTERFACE APPLICATIONS VCC VCC VCC VCC IN CML IN LVPECL /IN /IN IN SY58031U GND VCC VCC SY58031U CML /IN NC VREF-AC NC VT GND VCC GND 0.01µF SY58031U VREF-AC VREF-AC VCC VT 0.01µF Rpd VT For 2.5V, Rpd = 19Ω For 3.3V, Rpd = 50Ω Option: May connect VT to VCC. Figure 3a. DC-Coupled CML Input Interface Figure 3b. AC-Coupled CML Input Interface VCC VCC VCC VCC IN LVPECL IN /IN Rpd Rpd LVDS SY58031U GND /IN VT GND For 3.3V, Rpd = 100Ω For 2.5V, Rpd = 50Ω VREF-AC SY58031U GND NC VREF-AC NC VT VCC Figure 3d. AC-Coupled LVPECL Input Interface M9999-020707 [email protected] or (408) 955-1690 Figure 3e. LVDS Input Interface 6 Figure 3c. LVPECL Input Interface Precision Edge® SY58031U Micrel, Inc. CML OUTPUT TERMINATION Figure 4 and Figure 5 illustrate how to terminate a CML output using both the AC- and DC-coupled configuration. All outputs of the SY58031U are 50Ω with a 16mA current source. VCC VCC SY58031U SY58031U 50Ω 50Ω 50Ω Q 50Ω Q ZO = 50Ω ZO = 50Ω 50Ω 100Ω /Q /Q ZO = 50Ω 50Ω ZO = 50Ω DC bias per application 16mA 16mA GND GND Figure 4. CML DC-Coupled Termination Figure 5. CML AC-Coupled Termination RELATED MICREL PRODUCTS AND SUPPORT DOCUMENTATION Part Number Function Data Sheet Link SY58031U Ultra-Precision 1:8 CML Fanout Buffer with Internal I/O Termination http://www.micrel.com/product-info/products/sy58031u.shtml SY58032U Ultra-Precision 1:8 LVPECL Fanout Buffer with Internal Termination http://www.micrel.com/product-info/products/sy58032u.shtml SY58033U Ultra-Precision 1:8 400mV Fanout Buffer with Internal Termination http://www.micrel.com/product-info/products/sy58033u.shtml 32-MLF® Manufacturing Guidelines Exposed Pad Application Note www.amkor.com/products/notes_papers MLF_AppNote.pdf HBW Solutions http://www.micrel.com/product-info/as/solutions.shtml M9999-020707 [email protected] or (408) 955-1690 7 Precision Edge® SY58031U Micrel, Inc 32-PIN MicroLeadFrame® (MLF-32) Package EP- Exposed Pad Die CompSide Island Heat Dissipation Heat Dissipation VEE Heavy Copper Plane VEE Heavy Copper Plane PCB Thermal Consideration for 32-Pin MLF® Package (Always solder, or equivalent, the exposed pad to the PCB) Package Notes: 1. Package meets Level 2 qualification. 2. All parts are dry-packaged before shipment. 3. Exposed pads must be soldered to a ground for proper thermal management. 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 The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. 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 at Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2005 Micrel, Incorporated. M9999-020707 [email protected] or (408) 955-1690 8