sy89464u Micrel Semiconductor, sy89464u Datasheet
sy89464u
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sy89464u Summary of contents
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... General Description The SY89464U is a low jitter 1:10 LVPECL fanout buffer with a 2:1 differential input multiplexer (MUX) optimized for redundant applications. Unlike standard multiplexers, the SY89464U’s unique 2:1 Runt Pulse Eliminator (RPE) MUX prevents any short cycles or “runt” pulses during switchover. In addition, a unique Fail- ...
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Typical Application December 2007 Simplified Example Illustrating Runt Pulse Eliminator (RPE) when Primary Clock Fails 2 hbwhelp@micrel.com M9999-120607-B or (408) 955-1690 ...
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... Tape and Reel. Pin Configuration December 2007 Operating Type Range Industrial Industrial = 25°C, DC Electricals Only. A ® 44-Pin MLF (MLF-44) 3 Package Marking Finish SY89464U with Matte-Sn Pb-Free bar-line Indicator Pb-Free SY89464U with Matte-Sn Pb-Free bar-line Indicator Pb-Free M9999-120607-B hbwhelp@micrel.com or (408) 955-1690 Lead ...
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Pin Description Pin Number Pin Name 2, 5 IN0, /IN0 7, 10 IN1, /IN1 VREF-AC0 4, 9 VREF-AC1 3, 8 VT0, VT1 13, 15, 22, 23, 28 VCC 33, 34, 41, 43, 44 40, 39 Q0, /Q0 38, 37 Q1, ...
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Absolute Maximum Ratings Supply Voltage (V ) ..........................–0.5V to +4.0V CC Input Voltage (V ) ..................................–0. LVPECL Output Current (I ).................................... OUT Continuous ................................................. 50mA Surge........................................................ 100mA Input Current (I ) ........................................................ IN IN, /IN ....................................................... ±50mA ...
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LVPECL Outputs DC Electrical Characteristics V = 2.5V ±5% or 3.3V ±10 Symbol Parameter V Output HIGH Voltage Output LOW Voltage Output Voltage Swing OUT Differential Output ...
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AC Electrical Characteristics V = 2.5V ±5% or 3.3V ±10 Symbol Parameter f Maximum Operating Frequency MAX t Differential Propagation Delay pd In-to-Q In-to-Q SEL-to-Q SEL-to-Q t Differential Propagation Delay pd Tempco Temperature Coefficient t EN Set-up Time ...
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... Functional Description RPE MUX and Fail-Safe Input The SY89464U 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: 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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Case #2: Input Clock Failure: Switching from a selected clock stuck HIGH to a valid clock (RPE- enabled). If CLK1 fails HIGH before the RPE MUX selects CLK2 (using the SEL pin), the switchover will occur in three stages. Note: ...
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Case #3: Input Clock Failure: Switching from a selected clock stuck Low to a valid clock (RPE- enabled). If CLK1 fails LOW before the RPE MUX selects CLK2 (using the SEL pin), the switchover will occur in two stages. December ...
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Case #4: Input Clock Failure: Switching from the selected clock input stuck in an undetermined state to a valid clock input (RPE-enabled). If CLK1 fails to an undetermined state (e.g., amplitude falls below the 100mV (V single-ended input limit, or ...
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Enable Output (EN) Description The enable function is synchronous so that the outputs will be enabled/disabled when they are already in the LOW state. This avoids any chance of generating a runt pulse when the device is enabled/disabled as can ...
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... Power-On Reset (POR) Description The SY89464U 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 capacitor connected between V and the CAP pin (pin 12) controls the delay for CC the power-on reset function. ...
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Typical Operating Characteristics V = 3.3V, GND = 0V ” 300ps December 2007 = 50Ÿ –2V 25°C, unless otherwise stated M9999-120607-B hbwhelp@micrel.com or (408) 955-1690 ...
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Functional Characteristics V = 2.5V, GND = 0V, V • 400mV CC IN December 2007 , t /t ” 300ps 50Ÿ -2V 25°C, unless otherwise stated. A M9999-120607-B ...
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Single-Ended and Differential Swings Figure 1a. Single-Ended Voltage Swing Input and Output Stages Figure 2a. Simplified Differential Input Stage December 2007 Figure 1b. Differential Voltage Swing Figure 2b. Simplified Differential Output Stage 16 hbwhelp@micrel.com M9999-120607-B or (408) 955-1690 ...
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Input Interface Applications Figure 3a. LVPECL Interface (DC-Coupled) Figure 3d. CML Interface (AC-Coupled) December 2007 Figure 3b. LVPECL Interface (AC-Coupled) Figure 3e. LVDS Interface (DC-Coupled) 17 Option: may connect Figure 3c. CML Interface (DC-Coupled) M9999-120607-B ...
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PECL Output Interface Applications PECL has a high input impedance, a very low output impedance (open emitter), and a small signal swing which results in low EMI. PECL is ideal for driving 50Ω- and 100Ω-controlled impedance transmission lines. There are ...
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MicroLeadFrame Packages Notes: 1. Package meets Level 2 Moisture Sensitivity Classification. 2. All parts are dry-packed before shipment. 3. Exposed pad must be soldered to a ground for proper thermal management. MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA ...