Micrel, Inc. Precision Edge® SY58021U ® Precision Edge 4GHz, 1:4 LVPECL FANOUT BUFFER/ TRANSLATOR WITH INTERNAL TERMINATION SY58021U FEATURES Precision 1:4, LVPECL fanout buffer Guaranteed AC performance over temperature/ voltage: • >4GHz fMAX (clock) Precision Edge® DESCRIPTION • <100ps tr / tf Times • <300ps tpd • <15ps max skew Low jitter performance • <10pspp total jitter (clock) • <1psrms random jitter (data) • <10pspp deterministic jitter (data) Accepts an input signal as low as 100mV Unique input termination and VT pin accepts DC-coupled and AC-coupled differential inputs: LVPECL, LVDS, and CML 100k LVPECL compatible 800mV swing output Power supply 2.5V ±5% and 3.3V ±10% –40°C to +85°C temperature range Available in 16-pin (3mm × 3mm) MLF® package The SY58021U is a 2.5V/3.3V precision, high-speed, fully differential 1:4 LVPECL fanout buffer. Optimized to provide four identical output copies with less than 15ps of skew and less than 10pspp total jitter, the SY58021U can process clock signals as fast as 4GHz. The differential input includes Micrel’s unique, 3-pin input termination architecture interfaces to differential LVPECL, CML, and LVDS signals (AC- or DC-coupled) as small as 100mV without any level-shifting or termination resistor networks in the signal path. For AC-coupled input interface applications, an on-board output reference voltage (VREFAC) is provided to bias the VT pin. The outputs are 100k LVPECL compatible, with extremely fast rise/fall times guaranteed to be less than 100ps. The SY58021U 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 faster rise/fall times, or greater bandwidth, consider the SY58022U 1:4 fanout buffer with 400mV LVPECL output swing, or the SY58020U 1:4 CML fanout buffer. The SY58021U 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 ■ ■ ■ ■ All SONET and All GigE clock distribution Fibre Channel clock and data distribution Backplane distribution High-end, low skew, multiprocessor synchronous clock distribution FUNCTIONAL BLOCK DIAGRAM TYPICAL PERFORMANCE Q0 IN 50Ω 1.25GHz Output /Q0 VT 50Ω Q1 Amplitude /Q1 VREF-AC Q2 (200mV/div.) /IN /Q2 Q3 TIME (100ps/div.) /Q3 Precision Edge is a registered trademark of Micrel , Inc. MicroLeadFrame and MLF are registered trademarks of Amkor Technology, Inc. M9999-020207 [email protected] or (408) 955-1690 Rev.: E 1 Amendment: /0 Issue Date: February 2007 Precision Edge® SY58021U Micrel, Inc. GND Q0 /Q0 VCC PACKAGE/ORDERING INFORMATION 16 15 14 13 Ordering Information(1) VT 2 11 /Q1 VREF-AC 3 10 Q2 /IN 4 9 /Q2 5 6 7 8 VCC Q1 Q3 12 /Q3 1 GND IN 16-Pin MLF® (MLF-16) Part Number Package Type Operating Range Package Marking Lead Finish SY58021UMI MLF-16 Industrial 021U Sn-Pb SY58021UMITR(2) MLF-16 Industrial 021U Sn-Pb SY58021UMG(3) MLF-16 Industrial 021U with Pb-Free bar-line indicator Pb-Free NiPdAu SY58021UMGTR(2, 3) MLF-16 Industrial 021U with Pb-Free bar-line indicator Pb-Free NiPdAu 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 1, 4 IN, /IN Differential Input: This input pair receives the signal to be buffered. 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. 2 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. 3 VREF-AC 8, 13 VCC 5, 16 GND, Exposed Pad 14, 15 11, 12 9, 10 6, 7 /Q0, Q0, /Q1, Q1, /Q2, Q2, /Q3, Q3 M9999-020207 [email protected] or (408) 955-1690 Pin Function Reference Output Voltage: This output biases to VCC –1.2V. It is used when AC-coupling to differential inputs. Connect VREF-AC directly to the VT pin. Bypass with 0.01µF low ESR capacitor to VCC. See “Input Interface Applications” section. Positive Power Supply: Bypass with 0.1µF//0.01µF low ESR capacitors as close to the VCC pins as possible. Ground. Exposed pad must be connected to a ground plane that is the same potential as the ground pin. LVPECL Differential Output Pairs: Differential buffered output copy of the input signal. The output swing is typically 800mV Proper termination is 50Ω to VCC–2V at the receiving end. Unused output pairs may be left floating with no impact on jitter or skew. See “LVPECL Output Termination” section. 2 Precision Edge® SY58021U 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 LVPECL Output Current (IOUT) Continuous ............................................................. 50mA Surge .................................................................... 100mA Source or sink current on VT pin VT Current .......................................................... ±100mA Source or sink current on IN, /IN Input Current ........................................................ ±50mA Source or sink current on VREF-AC(4) VREF Current ....................................................... ±1.5mA Soldering, (20 seconds) ............................................ 260°C Storage Temperature Range (TS) ............ –65°C to +150°C Power Supply Voltage (VCC) ................. +2.375V to +3.60V Operating Temperature Range (TA) ........... –40°C to +85°C Package Thermal Resistance MLF® (θJA) Still-Air ............................................................. 60°C/W 500 lpfm ........................................................... 54°C/W MLF® (ψJB) Junction-to-Board Resistance(3) ...................... 33°C/W INPUT DC ELECTRICAL CHARACTERISTICS(5) TA= –40°C to 85°C Symbol Parameter Condition Min Typ Max Units VCC Power Supply Voltage VCC = 2.5V VCC = 3.3V 2.375 3.0 2.5 3.3 2.625 3.60 V V ICC Power Supply Current No load, VCC = max. 125 160 mA VIH Input HIGH Voltage IN, /IN VCC–1.2 VCC V VIL Input LOW Voltage IN, /IN 0 VIH –0.1 V VIN Input Voltage Swing IN, /IN; see Figure 1a. 0.1 1.7 V VDIFF_IN Differential Input Voltage Swing IN, /IN; see Figure 1b. 0.2 3.4 V RIN IN-to-VT Resistance 60 Ω VT IN IN-to-VT Voltage 1.28 V VREF-AC Output Reference Voltage 40 50 VCC–1.30 VCC–1.2 VCC–1.1 V LVPECL OUTPUT DC ELECTRICAL CHARACTERISTICS(5) VCC = 3.3V ±10% or 2.5 ±5%; RL= 50Ω to VCC–2V; TA= –40°C to 85°C, unless otherwise stated. Symbol Parameter Condition Min VOH Output HIGH Voltage VOL Output LOW Voltage VOUT Output Voltage Differential Swing see Figure 1a. 550 VDIFF_OUT Differential Output Voltage Swing see Figure 1b. 1100 Typ Max Units VCC–1.145 VCC–0.895 V VCC–1.945 VCC–1.695 V 780 1050 mV 1560 2100 mV Notes: 1. Permanent device damage may occur if ratings in the “Absolute Maximum Ratings” section are exceeded. This is a stress rating only and functional operation is not implied for 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. Thermal performance assumes exposed pad is soldered (or equivalent) to the device’s most negative potential on the PCB. 4. Due to the limited drive capability, use for input of the same package only. 5. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established. M9999-020207 [email protected] or (408) 955-1690 3 Precision Edge® SY58021U Micrel, Inc. AC ELECTRICAL CHARACTERISTICS VCC = 2.5V ±5% or 3.3V ±10%; RL = 50Ω to VCC–2V; TA= –40°C to +85°C, unless otherwise stated. Symbol Parameter Condition Min fMAX Maximum Operating Frequency VOUT ≥ 400mV Clock Propagation Delay tCHAN Channel-to-Channel Skew Note 7 tSKEW Part-to-Part Skew tJITTER Clock GHz 5 150 Units Gbps 220 300 ps 4 15 ps Note 8 50 ps Note 9 1 psRMS Total Jitter Note 10 10 psPP Random Jitter Note 11 2.5Gbps – 3.2Gbps 1 psRMS Deterministic Jitter Note 12 2.5Gbps – 3.2Gbps 10 psPP 110 ps Cycle-to-Cycle Jitter Data tr, tf Max 4 NRZ Data tpd Typ Output Rise/Fall Time 20% to 80% At full swing. 35 75 Notes: 7. Skew is measured between outputs of the same bank under identical transitions. 8. 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. 9. 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. 10. 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. 11. Random jitter is measured with a K28.7 comma detect character pattern, measured at 2.5Gbps/3.2Gbps. 12. Deterministic jitter is measured at 2.5Gbps/3.2Gbps with both K28.5 and 223–1 PRBS pattern TIMING DIAGRAM /IN IN /Q Q tpd SINGLE-ENDED AND DIFFERENTIAL SWINGS VDIFF_IN, VDIFF_OUT 1.6V VIN, VOUT 800mV Figure 1a. Single-Ended Voltage Swing M9999-020207 [email protected] or (408) 955-1690 Figure 1b. Differential Voltage Swing 4 Precision Edge® SY58021U Micrel, Inc. TYPCIAL OPERATING CHARACTERISTICS VCC = 2.5V, GND = 0, VIN = 100mV, TA = 25°C, unless otherwise stated. 3.5 194 3.0 700 2.5 600 SKEW (ps) AMPLITUDE (mV) 800 500 400 300 1.5 0.5 0 -60 -40 -20 0 12000 10000 8000 6000 4000 2000 0 100 0 2.0 1.0 200 20 40 60 80 100 TEMPERATURE (°C) FREQUENCY (MHz) Skew vs. Temperature 184 4.5 183 4.0 182 3.5 181 180 179 SKEW (ps) PROPAGATION DELAY (ps) Propagation Delay vs. Temperature 3.0 2.5 2.0 1.5 178 1.0 177 0.5 176 -60 -40 -20 0 20 40 60 80 100 TEMPERATURE (°C) M9999-020207 [email protected] or (408) 955-1690 Propagation Delay vs. Input Voltage Swing Skew vs. Temperature PROPAGATION DELAY (ps) Amplitude vs. Frequency 900 0 -60 -40 -20 0 20 40 60 80 100 TEMPERATURE (°C) 5 192 190 188 186 184 182 180 178 176 174 0 200 400 600 800 1000 1200 INPUT VOLTAGE SWING (mV) Precision Edge® SY58021U Micrel, Inc. FUNCTIONAL CHARACTERISTICS VCC = 2.5V, GND = 0, VIN = 100mV, TA = 25°C, unless otherwise stated. Amplitude (200mV/div.) 5GHz Output Amplitude (200mV/div.) 200MHz Output TIME (600ps/div.) TIME (25ps/div.) Amplitude (200mV/div.) 4GHz Output TIME (30ps/div.) M9999-020207 [email protected] or (408) 955-1690 6 Precision Edge® SY58021U Micrel, Inc. INPUT STAGE VCC IN 50Ω VT GND 50Ω /IN Figure 2. Simplified Differential Input Buffer INPUT INTERFACE APPLICATIONS VCC VCC VCC VCC IN LVPECL LVPECL /IN VT 0.01µF Rpd SY58021U Rpd VREF-AC 0.01µF Figure 3a. LVPECL Input Interface VCC For 3.3V, Rpd = 100Ω For 2.5V, Rpd = 50Ω Figure 3b. AC-Coupled LVPECL Input Interface VCC VCC IN CML /IN /IN SY58021U NC VT NC VREF-AC SY58021U VT VREF-AC 0.01µF Option: May connect VT to VCC Figure 3d. DC-Coupled CML Input Interface M9999-020207 [email protected] or (408) 955-1690 SY58021U NC VT NC VREF-AC VCC IN CML /IN VT NC For VCC = 2.5V, Rpd = 19Ω For VCC = 3.3V, Rpd = 50Ω LVDS Rpd VREF-AC VCC IN /IN SY58021U VDD VCC VCC IN VCC Figure 3e. AC-Coupled CML Input Interface 7 Figure 3c. LVDS Input Interface Precision Edge® SY58021U Micrel, Inc. LVPECL OUTPUT LVPECL output have very low output impedance (open emitter), and small signal swing which results in low EMI. LVPECL is ideal for driving 50Ω and 100Ω controlled impedance transmission lines. There are several techniques in terminating the LVPECL output, as shown in Figures 4 through 6. +3.3V* +3.3V +3.3V* SY58021U ZO = 50Ω R1 130Ω R1 130Ω +3.3V* SY58021U Z = 50Ω 50Ω ZO = 50Ω *Note. For +2.5V systems, R1 = 250Ω, R2 = 62.5Ω +3.3V Z = 50Ω 50Ω “destination” “source” R2 82Ω R2 82Ω 50Ω VT = VCC —2V VDD Rb* C1 (optional) 0.01µF * For +2.5V, Rb = 19Ω Notes: * For +3.3V, Rb = 46Ω to 50Ω 1. Power saving alternative to Thevenin termination. 2. Place termination resistors as close to destination inputs as possible. 3. Rb resistor sets the DC bias voltage, equal to VT. Figure 4. Parallel Termination-Thevenin Equivalent Figure 5. Parallel Termination (3-Resistor) +3.3V +3.3V VT = VCC –1.3V +3.3V Q R1 130Ω R1 130Ω R4 1kΩ +3.3V ZO = 50Ω /Q VT = VCC –2V R2 82Ω R2 82Ω R3 1.6kΩ Note 1. Unused output (/Q) must be terminated to balance the output. Note 2. For +2.5V systems: R1 = 250 , R2 = 62.5 , R3 = 1.25k , R4 = 1.2k . For +3.3V systems: R1 = 130 , R2 = 82 , R3 = 1k , R4 = 1.6k . Note 3. Unused output pairs (Q and /Q) may be left floating. Figure 6. Terminating Unused I/O RELATED MICREL PRODUCTS AND SUPPORT DOCUMENTATION Part Number Function Data Sheet Link SY58020U 6GHz, 1:4 CML Fanout Buffer/Translator Internal I/O Termnations http://www.micrel.com/product-info/products/sy58020u.shtml SY58021U 4GHz, 1:4 LVPECL Fanout Buffer/Translator with Internal Termination http://www.micrel.com/product-info/products/sy58021u.shtml SY58022U 5.5GHz, 1:4 Fanout Buffer/Translator w/400mV LVPECL Outputs and Internal Terminations http://www.micrel.com/product-info/products/sy58022u.shtml 16-MLF™ Manufacturing Guidelines Exposed Pad Application Note www.amkor.com/products/notes_papers/MLF_AppNote_0902.pdf HBW Solutions http://www.micrel.com/product-info/as/solutions.shtml M-0317 M9999-020207 [email protected] or (408) 955-1690 8 Precision Edge® SY58021U Micrel, Inc. 16-PIN MicroLeadFrame® (MLF-16) Package EP- Exposed Pad Die CompSide Island Heat Dissipation Heat Dissipation VEE Heavy Copper Plane VEE Heavy Copper Plane PCB Thermal Consideration for 16-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 TEL + 1 (408) 944-0800 FAX + 1 (408) 474-1000 WEB USA 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. M9999-020207 [email protected] or (408) 955-1690 9