SY89854U Precision Low Power 1:4 LVPECL Fanout Buffer/Translator with Internal Termination General Description The SY89854U is a 2.5V/3.3V precision, highspeed, fully differential 1:4 LVPECL fanout buffer. Optimized to provide four identical output copies with less than 20ps of skew and less than 10ps(pp) total jitter, the SY89854U can process clock signals as fast as 2GHz. The differential input includes Micrel's unique, patent pending 3-pin input termination architecture that interfaces to any differential signal (AC or DCcoupled) as small as 100mV (200mVpp) without any level shifting or termination resistor networks in the signal path. For AC-coupled input interface applications, an on-board output reference voltage (VREF-AC) is provided to bias the center-tap (VT) pin. The outputs are 800mV LVPECL, with fast rise/fall times guaranteed to be less than 180ps. The SY89854U operates from a 2.5V 5% supply or a 3.3V 10% supply and is guaranteed over the full industrial temperature range of -40C to +85C. The SY89854U is part of Micrel's high-speed, (R) Precision Edge product line. All support documentation can be found on Micrel's web site at: www.micrel.com. Typical Applications 200MHz (Q - /Q) Precision Edge (R) Features * Precision 1:4, LVPECL fanout buffer * Low power: 137mW (2.5V typ) * Guaranteed AC performance over temperature and supply voltage: - DC- to > 2GHz Clock fMAX - <340ps tpd - <180ps tr/tf time - <20ps max. skew * Ultra-low jitter design: - <1ps(rms) random jitter - <10ps(pp) deterministic jitter - <10ps(pp) total jitter (clock) * Unique patent pending input termination and VT pin accepts DC-coupled and AC-coupled inputs (CML, PECL, LVDS) * Typical 800mV (100k) LVPECL output swing * Power supply 2.5V 5% or 3.3V 10% * Industrial temperature range -40C to +85C * Available in ultra-small (3mm x 3mm) 16-pin QFN package Applications Output Swing (200mV/div.) * SONET and All GigE clock distribution * Fibre Channel clock and data distribution * Backplane distribution TIME (600ps/div.) United States Patent No. RE44,134 Precision Edge is a registered trademark of Micrel, Inc. August 2007 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Ordering Information(1) Part Number Package Type Operating Range Package Marking Lead Finish SY89854UMG QFN-16 Industrial 854U with Pb-free bar-line indicator Pb-Free NiPdAu QFN-16 Industrial 854U with Pb-free bar-line indicator Pb-Free NiPdAu (2) SY89854UMGTR Notes: 1. Contact factory for die availability. Dice are guaranteed at TA = 25C, DC Electricals Only. 2. Tape and Reel. Pin Configuration 16-Pin QFN Pin Description Pin Number Pin Name Pin Function IN, /IN Differential Input: This input pair is the signal to be buffered. These inputs accept AC- or DC-coupled differential signals as small as 100mV (200mVPP). Each pin of this pair internally terminates to a VT pin through 50. Note that this input will default to an indeterminate state if left open. Please refer to the "Input Interface Applications" section for more details. 2 VT Input Termination Center-Tap: Each side of the differential input pair terminates to this pin. The VT pin provides a center-tap to a termination network for maximum interface flexibility. See "Input Interface Applications" section for more details. 8,13 VCC Positive Power Supply. Bypass with 0.1F||0.01F low ESR capacitors as close to the VCC pin as possible. 15, 14 12, 11 10, 9 7, 6 Q0, /Q0 Q1, /Q1 Q2, /Q2 Q3, /Q3 Differential 100K LVPECL Output: These LVPECL outputs are the precision, low skew copies of the input signal. Terminate with 50 to V CC-2V. Unused output pairs may be left floating with no impact on jitter. See "Output Interface Applications" section. 5, 16 GND, Exposed Pad Ground. Ground pin and exposed pad must be connected to the same ground plane. VREF-AC Reference Voltage: This output biases to VCC-1.2V. It is used when AC coupling the inputs (IN, /IN). Connect VREF-AC to the VT pin. Bypass VREF-AF pin with a 0.01F low ESR capacitor to VCC. Maximum sink/source capability is 1.5mA. See "Input Interface Applications" section for more details. 1, 4 3 August 2007 2 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Functional Block Diagram August 2007 3 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Absolute Maximum Ratings(1) Operating Ratings(2) Supply Voltage (VCC) .......................... -0.5V to +4.0V Input Voltage (VIN) ..................................-0.5V to VCC LVPECL Output Current (IOUT) Continuous ................................................. 50mA Surge ........................................................ 100mA (3) Termination Current Source or sink current on VT .................... 50mA Input Current Source or sink current on IN, /IN .............. 50mA (3) VREF-AC Current Source or sink current ................................ 2mA Lead Temperature (soldering, 20sec.) ........... +260C Storage Temperature (Ts) ..................-65C to 150C Supply Voltage (VCC).................. +2.375V to +2.625V ......................................................+3.0V to +3.6V Ambient Temperature (TA) ................ -40C to +85C (4) Package Thermal Resistance QFN (JA) Still-Air ..................................................... 60C/W QFN (JB) Junction-to-Board .................................... 38C/W DC Electrical Characteristics (5) TA = -40C to +85C, unless otherwise stated. Symbol Parameter Condition VCC Power Supply ICC Power Supply Current RDIFF_IN Differential Input Resistance (IN, /IN) RIN Input Resistance (IN-to-VT) VIH Input High Voltage (IN, /IN) VIL Input Low Voltage (IN, /IN) VIN Input Voltage Swing (IN, /IN) See Figure 1a. VDIFF_IN Differential Input Voltage Swing (IN, /IN) See Figure 1b. VT_IN IN-to-VT Min Typ Max Units 2.375 2.5 2.625 V 3.0 3.3 3.6 V 55 78 mA 90 100 110 45 50 55 VCC -1.6 VCC V 0 VIH -0.1 V 0.1 1.7 V No load, max. VCC Note 6 0.2 V 1.28 V Notes: 1. Permanent device damage may occur if the 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. Package thermal resistance assumes exposed pad is soldered (or equivalent) to the devices most negative potential on the PCB. JA and JB are calculated based on a 4-layer board in still air, unless otherwise stated. 5. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established.\ 6. VIH (min) not lower than 1.2V. August 2007 4 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U LVPECL Outputs DC Electrical Characteristics(7) VCC = +2.5V 5% or +3.3V 10%; TA = -40C to + 85C; RL = 50 to VCC -2V, unless otherwise stated. Symbol Parameter Condition Min Typ Max Units VOH Output HIGH Voltage Q, /Q VCC-1.145 VCC-0.895 V VOL Output LOW Voltage Q, /Q VCC-1.945 VCC-1.695 V VOUT Output Voltage Swing Q, /Q See Figure 1a. 550 800 mV VDIFF-OUT Differential Output Voltage Swing Q,/Q See Figure 1b. 1100 1600 mV Note: 7. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established. August 2007 5 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U AC Electrical Characteristics(8) VCC = +2.5V 5% or +3.3V 10%; TA = -40C to + 85C, RL = 50 to VCC-2V, unless otherwise stated. Symbol Parameter Condition Min fMAX Maximum Operating Frequency Clock, VOUT 400mV 2.0 NRZ Data VIN 100mVpk Max Units 3.5 GHz 2.5 Gbps tpd Propagation Delay (IN-to-Q) tpd Tempco Differential Propagation Delay Temperature Coefficient tSKEW Output-to-Output Skew Note 9 Part-to-Part Skew Note 10 150 ps Random Jitter (RJ) Note 11 1 psRMS Deterministic Jitter (DJ) Note 12 10 psPP tJitter tr, tf 140 Typ 220 340 o 100 4 ps fs/ C 20 ps Cycle-to-Cycle Jitter Note 13 1 psRMS Total Jitter Note 14 10 psPP Output Rise/Fall Time (20% to 80%) At full output swing. 180 ps 50 100 Notes: 8. High-frequency AC-parameters are guaranteed by design and characterization. 9. Output-to-output skew is measured between outputs under identical conditions. 10. 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. 11. Random jitter is measured with a K28.7 character pattern, measured at 2.5Gbps. 12. DJ is measured at 2.5Gbps, with both K28.5 and 223 - 1 PRBS pattern. 13. 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. 14. 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. August 2007 6 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Typical Operating Characteristics VCC = 2.5V, VIN = 100mVpk, TA = 25C, unless otherwise stated. Amplitude vs. Frequency Propagation Delay vs. Temperature Propagation Delay vs. Input Voltage 222 900 228 800 226 220 700 224 218 600 222 216 500 220 214 400 218 212 300 216 210 200 214 208 100 200 1200 2200 3200 4200 5200 6200 FREQUENCY (MHz) 212 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 206 INPUT VOLTAGE (mV) August 2007 7 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Functional Characteristics VCC = 2.5V, VIN = 100mV, TA = 25C, unless otherwise stated. August 2007 8 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Single-Ended and Differential Swings Figure 1a. Singled-Ended Voltage Swing Figure1b. Differential Voltage Swing Timing Diagrams August 2007 9 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Input and Output Stages Figure 2b. Simplified LVPECL Output Stage Figure 2a. Simplified Differential Input Stage August 2007 10 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Input Interface Applications Option: may connect VT to VCC 3a. LVPECL Interface (DC-Coupled) 3b. LVPECL Interface (AC-Coupled) 3d. CML Interface (AC-Coupled) 3e. LVDS Interface August 2007 11 3c. CML Interface (DC-Coupled) M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U Output Interface Applications Note: For +2.5V systems, Rb = 19 For +3.3V systems, Rb = 50 Note: For +2.5V systems, R1 = 250, R2 = 82.5 Figure 4b. Parallel Termination (3-Resistor) Figure 4a. Parallel Thevenin-Equivalent Termination Related Product and Support Documentation Part Number Function Data Sheet Link SY58021U 4GHz, 1:4 LVPECL Fanout Buffer/Translator with Internal Termination www.micrel.com/product-info/products/sy58021u.shtml HBW Solutions New Products and Applications www.micrel.com/product-info/products/solutions.shtml August 2007 12 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690 Micrel, Inc. SY89854U 16-Pin QFN Package Notes: (1) Package meets Level 2 Moisture Sensitivity Classification. (2) All parts are dry-packaged before shipment. (3) Exposed pad 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 a Purchaser's own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. (c) 2005 Micrel, Incorporated. August 2007 13 M9999-082907-C hbwhelp@micrel.com or (408) 955-1690