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 ■ Low-jitter performance: • 75fsRMS phase jitter (typ) ■ Guaranteed AC performance over temperature and voltage: • Clock frequency range: DC to >6GHz • <60ps tr / tf time • <270ps tpd • <20ps ouput-to-output skew ■ 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 x 5mm) QFN 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 only 75fsRMS phase 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 Precision Edge is a registered trademark of Micrel, Inc. M9999-073010 [email protected] or (408) 955-1690 1 Rev.: F Amendment: /0 Issue Date: October 2011 Precision Edge® SY58031U Micrel, Inc PACKAGE/ORDERING INFORMATION Ordering Information(1) 32-Pin QFN (QFN-32) Part Number Package Operating Type Range Package Marking SY58031UMG(3) QFN-32 Industiral Pb-Free SY58031U with Pb-Free bar-line indicator SY58031UMGTR(2, 3) QFN-32 Industrial Pb-Free SY58031U with Pb-Free bar-line indicator Notes: 1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC electricals only. All devices are Pb-Free. 2. Tape and Reel. 3. Pb-Free package recommended for new designs. PIN DESCRIPTION Pin Number Pin Name Pin Function 3, 6 IN, /IN 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. 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 Ground. Exposed pad must be connected to a ground plane that is the same potential as the ground pin. GND, Exposed Pad 1, 8, 9, 16 VCC 18, 23, 25, 32 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 5 VREF-AC M9999-073010 [email protected] or (408) 955-1690 Positive Power Supply: Bypass with 0.1µF||0.01µF low ESR capacitors as close to the pins as possible. 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. 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) QFN (θJA) Still-Air.............................................................. 35°C/W QFN (ψJB) Junction-to-Board............................................. 20°C/W DC ELECTRICAL CHARACTERISTICS(5) TA= –40°C to +85°C Symbol Parameter Condition Min Typ Max Units 2.375 3.0 2.5 3.3 2.625 3.6 V V Power Supply Voltage VCC 2.5V nominal 3.3V nominal Power Supply Current ICC VCC = max. no lead. Includes current 265 330 through 50Ω pull-ups. VIH Input HIGH Voltage IN1, /IN1, Note 6 Input LOW Voltage IN1, /IN1 VIN VIL VCC–1.6 0 mA VCC V 1.7 V VIH–0.1 V Input Voltage Swing IN1, /IN1, see Figure 1a. 0.1 VDIFF_IN Differential Input Voltage Swing |IN0, /IN0|, |IN1, /IN1| IN1, /IN1, see Figure 1b. 0.2 V RIN In-to-VT Resistance 40 Ω VT IN 50 Max. In-to-VT (IN, /IN) 60 1.28 VCC–1.3 VCC–1.2 VCC–1.1 VREF-AC V 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 VOH Output HIGH Voltage Condition Min VOUT Output Voltage Swing see Figure 1a. Differential Voltage Swing see Figure 1b. ROUT Output Source Impedance VDIFF_OUT Typ VCC–0.020 Max Units VCC V 325 400 mV 650 800 mV 40 50 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. 6. VIH (min) not lower tha 1.2V. M9999-073010 [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 fMAX Maximum Operating Frequency tpd tpd tempco Propagation Delay Condition VOUT ≥ 200mV Clock (IN-to-Q) Min Typ Max 6 120 Differential Propagation Delay Temperature Coefficient 230 270 35 Units GHz ps fs/°C Output-to-Output (Within Device) tSKEW Part-to-Part tJITTER RMS Phase Jitter Note 8 7 20 Note 9 100 Output: 622MHz Integration Range: 12kHz - 20MHz 75 ps ps tr, tf 20% to 80%, at full output swing ps Output Rise/Fall Time 20 45 60 fs 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. Phase Noise RMS Phase Jitter (Random) 12kHz to 20MHz: 75fs (Typical) Phase Noise Plot: 622MHz @ 3.3V M9999-073010 [email protected] or (408) 955-1690 4 Precision Edge® SY58031U Micrel, Inc Single-Ended and Differential SwingS Figure 1a. Single-Ended Voltage Swing Figure 1b. Differential Voltage Swing TIMING DIAGRAM M9999-073010 [email protected] or (408) 955-1690 5 Precision Edge® SY58031U Micrel, Inc. TYPICAL OPERATING CHARACTERISTICS VCC = 2.5V, GND = 0, VIN = 100mV, TA = 25°C, unless otherwise stated. M9999-073010 [email protected] or (408) 955-1690 6 Precision Edge® SY58031U Micrel, Inc INPUT BUFFER Figure 2. Simplified Differential Input Buffer INPUT INTERFACE APPLICATIONS Figure 3a. DC-Coupled CML Input Interface Figure 3b. AC-Coupled CML Input Interface Figure 3d. AC-Coupled LVPECL Input Interface Figure 3e. LVDS Input Interface Option: May connect VT to VCC. M9999-073010 [email protected] or (408) 955-1690 7 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. 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 SY58032U SY58033U Ultra-Precision 1:8 CML Fanout Buffer with Internal I/O Termination Ultra-Precision 1:8 LVPECL Fanout Buffer with Internal Termination Ultra-Precision 1:8 400mV Fanout Buffer with Internal Termination http://www.micrel.com/product-info/products/sy58031u.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 M9999-073010 [email protected] or (408) 955-1690 http://www.micrel.com/product-info/products/sy58032u.shtml http://www.micrel.com/product-info/products/sy58033u.shtml 8 Precision Edge® SY58031U Micrel, Inc 32-pin QFN (QFN-32) PCB Thermal Consideration for 32-Pin QFN 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. M9999-073010 [email protected] or (408) 955-1690 9