sy89837u Micrel Semiconductor, sy89837u Datasheet
sy89837u
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sy89837u Summary of contents
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... PRECISION 1:8 LVPECL FANOUT BUFFER WITH 2:1 RUNT PULSE ELIMINATOR INPUT MUX DESCRIPTION The SY89837U is a low jitter, low skew, high-speed 1:8 fanout buffer with a unique, 2:1 differential input multiplexer (MUX) optimized for clock redundant switchover applications. Unlike standard multiplexers, the SY89837U unique 2:1 runt pulse eliminator (RPE) input MUX prevents any short cycles or “ ...
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... Elimination Logic SEL Select Primary Select Secondary Runt pulse eliminated Switchover from output Circuit When Primary Clock Fails Outputs SEL Precision Edge 1:8 Fanout Q0 /Q0 Q1 /Q1 Q2 /Q2 Q3 /Q3 Q4 /Q4 Q5 /Q5 Q6 /Q6 Q7 /Q7 occurs ® SY89837U ...
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... The purpose is to ensure the internal RPE logic starts the RPE function will be disabled and the multiplexer will CC 3 Precision Edge SY89837U Package Range Marking SY89837U SY89837U SY89837U with Pb-Free bar-line indicator SY89837U with Pb-Free bar-line indicator = 25°C, DC Electricals only. A ® Lead Finish Sn-Pb Sn-Pb Pb-Free ...
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... Micrel, Inc. DETAILED FUNCTIONAL DESCRIPTION RPE MUX and Fail-Safe Input The SY89837U is optimized for clock switchover applications where switching from one clock to another clock without runt pulses (short cycles) is required. It features two unique circuits: 1. Runt-Pulse Eliminator (RPE) Circuit The RPE MUX provides a “glitchless” switchover between two clocks and prevents any runt pulses from occurring during the switchover transition ...
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... CLK2 (1) Figure 3. Timing Diagram 2 • Stage 1: The output will remain LOW for a limited number of falling edges of CLK2. • Stage 2: The output will follow CLK2. Stage 1 Select CLK2 falling edges of CLK2 Figure 4. Timing Diagram 3 5 ® Precision Edge SY89837U Stage 3 Stage 2 ...
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... No ringing and no undetermined state will occur at the output under these conditions. POWER-ON RESET (POR) DESCRIPTION The SY89837U includes an internal power-on reset (POR) function to ensure the RPE logic starts- known logic state once the power-supply voltage is stable. An external ...
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... CC ) ......................... –40°C to +85° Min Typ 2.375 3.0 115 100 1 0.2 0.4 100 V –1.3 V –1 ® SY89837U Max Units 2.625 V 3.6 V 160 mA 55 ý 110 ý –0 200 mV 1.8 V –1 uses a 4-layer ...
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... T = –40°C to +85°C, unless noted Condition See Figure 1a. See Figure 1b. (7) –2V –40°C to +85°C, unless noted Condition 8 ® Precision Edge SY89837U Min Typ Max Units V –1.145 V –0.895 –1.945 V –1.695 ...
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... Typ 1.5 2.0 525 700 115 20 70 120 where T is the time between rising edges of the output n–1 12 output edges will deviate by more than the V DIFF_IN 1600mV (typical) ® SY89837U Max Units GHz 975 ps 17 cycles 1000 ps fs/° 200 RMS ...
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... V = 400mV IN PK 100 0 0 100 200 300 400 500 600 INPUT RISE/FALL TIME (ps) Output Swing vs. Frequency 800 750 700 650 600 550 500 450 400 0 500 1000 1500 2000 2500 3000 FREQUENCY (MHz) ® SY89837U ...
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... Micrel, Inc. OPERATING CHARACTERISTICS (CONTINUED) 200MHz Clock TIME (200ps/div.) 1GHz Clock TIME (150ps/div.) M9999-022007 hbwhelp@micrel.com or (408) 955-1690 622MHz Clock TIME (200ps/div.) 1.5GHz Clock TIME (100ps/div.) 11 ® Precision Edge SY89837U ...
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... For 2.5V 50Ω. pd Figure 3b. LVPECL Interface (AC-Coupled LVDS /IN SY89837U GND REF-AC Figure 3e. LVDS Interface 12 ® Precision Edge SY89837U CML /IN SY89837U GND REF-AC Option: may connect Figure 3c. CML Interface (DC-Coupled) ...
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... M9999-022007 hbwhelp@micrel.com or (408) 955-1690 V CC +3.3V R1 +3.3V R2 GND GND GND Figure 4b. Parallel Termination (3-Resistors) Data Sheet Link www.amkor.com/product/notes_papers/MLFAppNote.pdf www.micrel.com/product-info/products/solutions.shtml 13 Precision Edge +3. 50Ω 50Ω 0 50Ω 50Ω GND +3.3V C1 (optional) 50Ω 0.01µF For V = +3.3V For V = +2.5V ® SY89837U = 50Ω 19Ω. b ...
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... Heavy Copper Plane Heavy Copper Plane PCB Thermal Consideration for 32-Pin MLF + 1 (408) 474-1000 FAX Micrel for any damages resulting from such use or sale. © 2005 Micrel, Incorporated. 14 Package EP- Exposed Pad Die ® Package http://www.micrel.com WEB ® Precision Edge SY89837U ...