1:6 LVPECL FANOUT BUFFER

Micrel 4.5GHz, 1:6 LVPECL FANOUT BUFFER w/ 2:1 MUX INPUT AND INTERNAL TERMINATION Precision Edge™ SY58035U Precision Edge™ SY58035U FEATURES s Provides 6 ultra-low skew copies of the selected input Precision Edge™ s 2:1 MUX input included for clock switchover applications DESCRIPTION s Guaranteed AC performance over temperature and voltage: The SY58035U is a 2.5V/3.3V precision, high-speed, 1:6 • Clock frequency range: DC to > 4.5GHz fanout capable of handling clocks up to 4.5GHz. A differential • < 350ps IN-to-OUT tpd 2:1 MUX input is included for redundant clock switchover • < 110ps tr / tf times applications. • < 20ps skew (output-to-output) The differential input includes Micrel’s unique, 3-pin input s Ultra-low jitter design: termination architecture that allows the device to interface • < 1psrms random jitter to any differential signal (AC- or DC-coupled) as small as • < 10psp-p total jitter (clock) 100mV without any level shifting or termination resistor • < 1psrms cycle-to-cycle jitter networks in the signal path. The outputs are LVPECL (100k, • < 0.7psrms crosstalk-induced jitter temperature compensated), with extremely fast rise/fall times guaranteed to be less than 110ps. s Low supply voltage operation: 2.5V and 3.3V The SY58035U operates from a 2.5V ±5% supply or a s Unique input termination and VT pin accepts DC3.3V ±10% supply and is guaranteed over the full industrial coupled and AC-coupled inputs (CML, PECL, LVDS) temperature range of –40°C to +85°C. For applications that s Unique input isolation design minimizes crosstalk require CML outputs, consider the SY58034U or for 400mV s 100k LVPECL compatible output swing www.DataSheet4U.com LVPECL outputs the SY58036U. The SY58035U is part of s –40°C to +85°C temperature range Micrel’s high-speed, Precision Edge™ product line. s Available in 32-pin (5mm × 5mm) MLF™ package All support documentation can be found on Micrel’s web site at www.micrel.com. APPLICATIONS s s s s Redundant clock distribution All SONET/SDH clock/data distribution All Fibre Channel distribution All Gigabit Ethernet clock distribution FUNCTIONAL BLOCK DIAGRAM 1:6 Fanout Q0 /Q0 IN0 50Ω VT0 50Ω /IN0 VREF-AC0 IN1 50Ω VT1 50Ω /IN1 VREF-AC1 SEL (TTL/CMOS) 1 S 0 2:1 Mux Q1 /Q1 Q2 Mux /Q2 Q3 /Q3 Q4 /Q4 Q5 /Q5 Precision Edge is a trademark of Micrel, Inc. MLF and MicroLeadFrame are trademarks of Amkor Technology, Inc. M9999-121603 Rev.: A Amendment: /0 1 Issue Date: December 2003 Micrel Precision Edge™ SY58035U PACKAGE/ORDERING INFORMATION GND SEL VCC Q0 /Q0 Q1 /Q1 VCC Ordering Information(1) GND VCC Q2 /Q2 Q3 /Q3 VCC GND IN0 VT0 VREF-AC0 /IN0 /IN1 VREF-AC1 VT1 IN1 1 2 3 4 5 6 7 8 32 3130 29 28 27 26 25 24 23 22 21 20 19 18 17 9 10 11 12 13 14 15 16 GND NC VCC /Q5 Q5 /Q4 Q4 VCC Part Number SY58035UMI SY58035UMITR(2) Notes: Package Type MLF-32 MLF-32 Operating Range Industrial Industrial Package Marking SY58035U SY58035U 1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC electricals only. 2. Tape and Reel. 32-Pin MLF™ PIN DESCRIPTION Pin Number 1, 4 8, 5 Pin Name IN0, /IN0 IN1, /IN1 Pin Function Differential Input: This input pairs are the differential signal inputs to the device. These inputs accept AC- or DC-coupled signals as small as 100mV. Each pin of a pair internally terminates to a VT pin through 50Ω. Note that these inputs will default to an indeterminate state if left open. Please refer to the “Input Interface Applications” section for more details. Input Termination Center-Tap: Each side of the differential input pair terminates to a VT pin. The VT0 and VT1 pins provide a center-tap to a termination network for maximum interface flexibility. See “Input Interface Applications” section for more details. This single-ended TTL/CMOS compatible input selects the inputs to the multiplexer. Note that this input is internally connected to a 25kΩ pull-up resistor and will default to a logic HIGH state if left open. The MUX select switchover function is asynchronous. Switching must occur within setup/hold time in order to prevent short cycles. No connect. Positive Power Supply: Bypass with 0.1µF0.01µF low ESR capacitors. Differential Outputs: These 100k (temperature compensated) LVPECL output pairs are low skew copies of the selected input. Unused output pins may be left floating. Please refer to the “Truth Table” for details. 2, 7 VT0, VT1 31 SEL 10 11, 16, 18, 23, 25, 30 29, 28 27, 26 22, 21 20, 19 15, 14 13, 12 9, 17, 24, 32 3, 6 NC VCC Q0, /Q0, Q1, /Q1, Q2, /Q2, Q3, /Q3, Q4, /Q4, Q5, /Q5 GND, Exposed Pad VREF-AC0 VREF-AC1 Ground: Ground pin and exposed pad must be connected to the same ground plane. Reference Voltage: This output biases to VCC–1.2V. It is used for AC-coupling inputs (IN, /IN). Connect VREF-AC directly to the VT pin. Bypass with 0.01µF low ESR capacitor to VCC. See “Input Interface Applications” section. Maximum sink/source is ±0.5mA. TRUTH TABLE SEL 0 1 IN0 Input Selected IN1 Input Selected M9999-121603 2 Micrel Precision Edge™ SY58035U Absolute Maximum Ratings(1) Power Supply Voltage (VCC ) ...................... –0.5V to +4.0V Input Voltage (VIN) ......................................... –0.5V to VCC LVPECL Output Current (IOUT) Continuous ............................................................. 50mA Surge .................................................................... 100mA Termination Current(3) Source or sink current on VT pin ........................ ±100mA Input Current Source or sink current on IN, /IN pin .................... ±50mA Lead Temperature (soldering, 10 sec.) ..................... 220°C Storage Temperature Range (TS ) ........... –65°C to +150°C Operating Ratings(2) Power Supply Voltage (VCC) ............... +2.375V to +2.625V ............................................................ +3.0V to +3.6V 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, unless otherwise stated. Symbol VCC ICC RDIFF_IN RIN VIH VIL VIN VDIFF_IN VT IN VREF-AC 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 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 table after thermal equilibrium has been established. 6. VIH (min), not lower than 1.2V. Parameter Power Supply Voltage Condition VCC = 2.5V VCC = 3.3V No load, max. VCC Min 2.375 3.0 Typ 2.5 3.3 185 Max 2.625 3.6 250 120 60 VCC VIH–0.1 1.7 Units V V mA Ω Ω V V V mV Power Supply Current Differential Input Resistance (IN-to-/IN) Input Resistance (IN-to-/IN) Input HIGH Voltage (IN-to-/IN) Input LOW Voltage (IN-to-/IN) Input Voltage Swing (IN-to-/IN) Differential Input Voltage Swing (IN-to-/IN) IN to VT (IN-to-/IN) Reference Voltage 80 40 Note 6 VCC–1.6 0 See Figure 1a See Figure 1b 0.1 0.2 100 50 1.28 VCC–1.3 VCC–1.2 VCC–1.1 V V M9999-121603 3 Micrel Precision Edge™ SY58035U LVPECL OUTPUT DC ELECTRICAL CHARACTERISTICS(7) VCC = 2.5V ±5% or 3.3V ±10%; TA= –40°C to +85°C; RL = 50Ω to VCC–2V, unless otherwise stated. Symbol VOH VOL VOUT VDIFF_OUT Parameter Output HIGH Voltage Output LOW Voltage Output Differential Swing Differential Output Voltage Swing See Figure 1a See Figure 1b Condition Min VCC–1.145 VCC–1.945 550 1.1 800 1.6 Typ Max VCC–0.895 VCC–1.695 Units V V mV V LVTTL/CMOS DC ELECTRICAL CHARACTERISTICS(7) VCC = 2.5V ±5% or 3.3V ±10%; TA= -40°C to 85°C, unless otherwise stated. Symbol VIH VIL IIH IIL Note: 7. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established. Parameter Input HIGH Voltage Input LOW Voltage Input HIGH Current Input LOW Current Condition Min 2.0 Typ Max Units V 0.8 40 –300 V µA µA M9999-121603 4 Micrel Precision Edge™ SY58035U AC ELECTRICAL CHARACTERISTICS(8) VCC = 2.5V ±5% or 3.3V ±10%; TA= –40°C to 85°C, RL = 50Ω to VCC–2V, unless otherwise stated. Symbol fMAX tpd Parameter Maximum Operating Frequency Differential Propagation Delay (IN0 or IN1-to-Q) (SEL-to-Q) ∆tpd Tempco tSKEW Differential Propagation Delay Temperature Coefficient Output-to-Output Part-to-Part tJITTER Clock Cycle-to-Cycle Jitter Random Jitter (RJ) Total Jitter (TJ) Adjacent Channel Crosstalk-Induced Jitter tr, tf Notes: 8. High frequency AC electricals are guaranteed by design and characterization. 9. Output-to-output skew is measured between outputs under identical input 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. 11. 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. 12. Random jitter is measured with a K28.7 comma detect character pattern, measured at 2.5Gbps to 3.2Gbps. 13. Total jitter definition: with an ideal clock input of frequency ≤ fMAX, no more than one output edge in 1012 output e