SY56028XR Low Voltage 1.2V/1.8V/2.5V CML 4:1 MUX with 1:2 FANOUT 6.4Gbps with EQUALIZATION . General Description The SY56028XR is a fully differential, low voltage Precision Edge® 1.2V/1.8V/2.5V CML 4:1 MUX, with input equalization, Features and integrated 1:2 Fanout Buffer. The SY56028XR can process clock signals as fast as 4.5GHz or data patterns • 1.2V/1.8V/2.5V CML 4:2 MUX with input equalization. up to 6.4Gbps. • Guaranteed AC performance over temperature and The differential input includes Micrel’s unique 3-pin input voltage: termination architecture that interfaces to DC-coupled – DC-to > 6.4Gbps throughput 2.5V/3.3V LVPECL, 1.2V/1.8V/2.5V CML or LVDS – <360ps propagation delay (IN-to-Q) differential signals. For AC-coupled input applications, – <15ps within-device skew an internal voltage reference is provided for input bias. Input voltages as small as 200mV (400mV ) are applied • Ultra-low jitter design pp before the 9, 18 or 27-inch FR4 transmission line. – <0.8ps random jitter RMS The SY56028XR operates from a 2.5V ±5% core supply – <10ps deterministic jitter PP and a 1.2V, 1.8V or 2.5V ±5% output supply and is • 2.5V ±5% , 1.8/1.2V ±5% power supply operation guaranteed over the full industrial temperature range • Industrial temperature range: –40°C to +85°C (–40°C to +85°C). The SY56028XR is part of Micrel’s • Available in 32-pin (5mm x 5mm) QFN package high-speed, Precision Edge® product line. Data sheets and support documentation can be found on Micrel’s web site at: www.micrel.com. Functional Block Diagram Applications • Data Distribution • SONET clock and data distribution • Fiber Channel clock and data distribution • Gigabit Ethernet clock and data distribution Precision Edge is a registered trademark of Micrel, 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 April 2010 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR (1) Ordering Information Part Number Package Operating Package Marking Lead Type Range Finish SY56028XRMG QFN-32 Industrial SY56028X with Pb-Free NiPdAu bar-line indicator Pb-Free SY56028XRMGTR(2) QFN-32 Industrial SY56028X with Pb-Free NiPdAu bar-line indicator Pb-Free Notes: 1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC Electricals only. 2. Tape and Reel. Pin Configuration 32-Pin QFN April 2010 2 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR Pin Description Pin Number Pin Name Pin Function 1,3 IN0, /IN0 Differential Inputs: Accepts differential signals as small as 200mV (400mVPP) applied to the input of a 9, 18 or 27 inch 6mil FR4 stripline transmission line. See 5,7 IN1, /IN1 “Input and Output Stage” section for details of this input. 25,27 IN2, /IN2 29,31 IN3, /IN3 2 VT0 Input Termination Center-Tap: Each side of the differential input pair terminates to the VT pin. This pin provides a center-tap to a termination network for maximum 6 VT1 interface flexibility. An internal high impedance resistor divider biases VT to allow 26 VT2 input AC coupling. For AC coupling, bypass VT with 0.1µF low ESR capacitor to 30 VT3 VCC. See “Input Interface Applications” subsection and Figure 2a. 19 EQ Three level input for equalization control. 15 SEL0 Single-ended TTL/CMOS compatible input selects the inputs to the multiplexer. This input is internally connected to a 25kΩ pull-up resistor and will default to a logic 18 SEL1 HIGH state if left open. Input logic threshold is VCC/2. See “Truth Table” for select control. 16,17 VCC Positive Power Supply: Bypass with 0.1uF//0.01uF low ESR capacitors as close to the VCC pin as possible. Supplies the input and core circuitry. 10,13,20,23 VCCO Output Supply: Bypass with 0.1uF//0.01uF low ESR capacitors as close to the VCCO pin as possible. Supplies the output buffers. 4,8,9,24,28,32 GND, Ground: Exposed pad must be connected to a ground plane that is the same potential as the ground pins. Exposed pad 12,11 Q0, /Q0 CML Differential Output Pair: Differential buffered copy of the input signal. The output swing is typically 390mV. See “Functional Description” subsection for 22,21 Q1, /Q1 termination information. Truth Table EQ Input Equalization FR4 6mil Stripline LOW 9 “ FLOAT 18” HIGH 27” SEL1 SEL0 0 0 IN0 Input Selected 0 1 IN1 Input Selected 1 0 IN2 Input Selected 1 1 IN3 Input Selected April 2010 3 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR (1) (2) Absolute Maximum Ratings Operating Ratings Supply Voltage (V ) ............................... –0.5V to +3.0V Supply Voltage (V ) ........................... 2.375V to 2.625V CC cc Supply Voltage (V ) ............................. –0.5V to +3.0V (V )………………..….1.14V to 2.625V CCO cco V -V ................................................................ <1.8V Ambient Temperature (T ) ................... –40°C to +85°C CC CCO A V -V ............................................................... <0.5 V Package Thermal Resistance(3) CCO CC Input Voltage (V ) ............................. –0.5V to V +0.4V QFN IN CC CML Output Voltage (V ) ............................ 0.6V to 3V Still-air (θ ) ............................................ 50°C/W OUT JA Current (VT) Junction-to-board (ψJB) ......................... 20°C/W Source or sink on VT pin ............................. ±100mA Input Current Source or sink Current on (IN, /IN) ................ ±50mA Maximum operating Junction Temperature .......... 125°C Lead Temperature (soldering, 20sec.) .................. 260°C Storage Temperature (T ) .................... –65°C to +150°C s (4) DC Electrical Characteristics T = –40°C to +85°C, unless otherwise stated. A Symbol Parameter Condition Min Typ Max Units VCC Power Supply Voltage Range VCC 2.375 2.5 2.625 V VCCO 1.14 1.2 1.26 V VCCO 1.7 1.8 1.9 V VCCO 2.375 2.5 2.625 V ICC Power Supply Current Max. VCC 110 140 mA ICCO Power Supply Current No Load. VCCO 32 42 mA RDIFF_IN Differential Input Resistance 90 100 110 Ω (IN-to-/IN) VIH Input HIGH Voltage IN, /IN (IN, /IN) 1.2 VCC+0.4 V VIL Input LOW Voltage IN, /IN (IN, /IN) 0 VIH–0.2 V VIN Input Voltage Swing See Figure 3a, Note 5, applied to 0.2 1.0 V (IN, /IN) input of transmission line. VDIFF_IN Differential Input Voltage Swing See Figure 3b, Note 5, applied to 0.4 2.0 V (|IN - /IN|) input of transmission line. VT_IN Voltage from Input to VT 1.28 V 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. Package thermal resistance assumes exposed pad is soldered (or equivalent) to the device's most negative potential on the PCB. ψJB and θJA values are determined for a four-layer board in still-air number, unless otherwise stated. 4. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established. 5. VIN (max) is specified when VT is floating. April 2010 4 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR (6) CML Outputs DC Electrical Characteristics V = 1.14V to 1.26V R = 50Ω to V . CCO L CCO V = 1.7V to 1.9V, 2.375V to 2.625V, R = 50Ω to V or 100Ω across the outputs. CCO L CCO V = 2.375V to 2.625V; T = –40°C to +85°C, unless otherwise stated. CC A Symbol Parameter Condition Min Typ Max Units VOH Output HIGH Voltage RL = 50Ω to VCCO VCC-0.020 VCC-0.010 VCC V VOUT Output Voltage Swing See Figure 3a 300 390 475 mV VDIFF_OUT Differential Output Voltage Swing See Figure 3b 600 780 950 mV ROUT Output Source Impedance 45 50 55 Ω (6) LVTTL/CMOS DC Electrical Characteristics V = 2.375V to 2.625V; T = –40°C to +85°C, unless otherwise stated. CC A Symbol Parameter Condition Min Typ Max Units VIH Input HIGH Voltage 2.0 VCC V VIL Input LOW Voltage 0.8 V IIH Input HIGH Current -125 30 µA IIL Input LOW Current -300 µA (6) Three Level EQ Input DC Electrical Characteristics V = 2.375V to 2.625V; T = –40°C to +85°C, unless otherwise stated. CC A Symbol Parameter Condition Min Typ Max Units VIH Input HIGH Voltage VCC-0.3 VCC V VIL Input LOW Voltage 0 VEE+0.3 V IIH Input HIGH Current VIH = VCC 400 µA IIL Input LOW Current VIL = GND -480 µA Note: 6. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established. April 2010 5 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR AC Electrical Characteristics V = 1.14V to 1.26V R = 50Ω to V . CCO L CCO V = 1.7V to 1.9V, 2.375V to 2.625V, R = 50Ω to V or 100Ω across the outputs. CCO L CCO V = 2.375V to 2.625V; T = –40°C to +85°C, unless otherwise stated. CC A Symbol Parameter Condition Min Typ Max Units fMAX Maximum Frequency NRZ Data 6.4 Gbps VOUT > 200mV (Clock) 4.5 GHz tPD Propagation Delay (IN-to-Q) N o t e 7 , F i g u r e 1 a 210 280 360 ps (SEL-to-Q) F i g u r e 1 b 1 ns tSkew Output-to-Output Skew Note 8 3 15 ps Part-to-Part Skew Note 9 100 ps tJitter Data Random Jitter Note 10 0.8 psRMS Data Deterministic Jitter Note 11 10 psPP tR tF Output Rise/Fall Time At full output swing. 30 55 85 ps (20% to 80%) Duty Cycle Differential I/O 45 55 % Notes: 7. Propagation delay is measured with no attenuating transmission line connected to the input. 8. Output-to-Output skew is the difference in time between both outputs under identical input transition, temperature and power supply. 9. Part-to-part skew is defined for two parts with identical power supply voltages at the same temperature and no skew at the edges at the respective inputs. 10. Random jitter is additive jitter. 11. Deterministic jitter is measured with 223–1 PRBS pattern. April 2010 6 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR Functional Description CML Output Termination with VCCO 1.2V CML Output Termination with VCCO 1.8V, 2.5V For VCCO of 1.2V, Figure 5a, terminate the output For VCCO of 1.8V or 2.5V, Figure 5a/b, terminate with with 50 Ohms to 1.2V, not 100 ohms differentially either 50 ohms to 1.8V or 100 ohms differentially across the outputs. If AC coupling is used, Figure 5d, across the outputs. AC-or DC-coupling is fine. For best terminate into 50 ohms to 1.2V before the coupling signal integrity, terminate any unused output pairs. capacitor and then connect to a high value resistor to a reference voltage. Any unused output pair with VCCO at 1.2V needs to be terminated, do not leave floating. Timing Diagrams Figure 1a. IN-to-Q Timing Diagram Figure 1b. SEL-to-Q Timing Diagram (Qx state can be high or low depending on input data) April 2010 7 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR Input and Output Stage Figure 2a. Simplified Differential Input Buffer Figure 2b. Simplified CML Output Buffer Single-Ended and Differential Swings Figure 3a. Single-Ended Swing Figure 3b. Differential Swing April 2010 8 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR Input Interface Applications Figure 4a. CML Interface Figure 4b. CML Interface Figure 4c. CML Interface 100 Ω Differential 50 Ω to Vcc (AC-Coupled) (DC-Coupled, 1.8V, 2.5V) (DC-Coupled, 1.2V,1.8V,2.5V) *See note in Functional Description for 1.2V CML driver with AC-Coupling Figure 4d. LVPECL Interface Figure 4e. LVPECL Interface Figure 4f. LVDS Interface (AC-Coupled) (DC-Coupled 2.5V and 3.3V) April 2010 9 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR CML Output Termination Figure 5a. 1.2V, 1.8V, 2.5V CML DC-Coupled Termination Figure 5b. 1.8V, 2.5V CML DC-Coupled Termination Figure 5c. CML AC-Coupled Termination Figure 5d. CML AC-Coupled Termination VCCO 1.8V, 2.5V only VCCO 1.2V only April 2010 10 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690

Micrel, Inc. SY56028XR Package Information 32-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 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. © 2010 Micrel, Incorporated. April 2010 11 M9999-040810-A hbwhelp@micrel.com or (408) 955-1690