VSC8121QI VITESSE [Vitesse Semiconductor Corporation], VSC8121QI Datasheet
VSC8121QI
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VSC8121QI Summary of contents
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Data Sheet VSC8121 Features • Monolithic Phase Locked Loop • On-Chip LC Oscillator • On-Chip Loop Filter • TTL/CMOS Reference Clock • Selectable Reference General Description The VSC8121 is a monolithic Phase Locked Loop (PLL) based clock generator designed for ...
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SONET/SDH Clock Generator Applications Information High-Speed Clock Output The differential clock output waveforms produced by the VSC8121 are sinusoidal in nature, by design. This typically results in less noise generation than square pulses in most customer applications. Figure 1 ...
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Data Sheet VSC8121 Figure 2: High-Speed Clock Output Diagram Pre-Driver Figure 3: Example High-Speed CML Clock Output Terminations 1) CO/CON 2) CO/CON 3) CO/CON G52163-0, Rev 4.2 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 04/16/01 ...
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SONET/SDH Clock Generator Reference Clock Input The input stage at the REFCLK input pin consists of ESD protection, followed by a current limiting circuit which precedes a driver responsible for providing the signal to the phase frequency detector. As ...
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Data Sheet VSC8121 AC Characteristics Table 2: AC Characteristics Parameter Description T High-speed output clock period CLK RC Reference clock duty cycle d RC Reference clock frequency (selectable Reference clock frequency tolerance RC t Jitter generation jitter NOTE: ...
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SONET/SDH Clock Generator DC Characteristics Table 3: Low Speed I/O Parameter Description V Output HIGH voltage (TTL Output LOW voltage (TTL Input HIGH voltage (TTL Input LOW voltage (TTL Input HIGH ...
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Data Sheet VSC8121 Absolute Maximum Ratings Power Supply Voltage (V ) Potential to GND ............................................................................-0 +4 TTL Input Voltage Applied ..........................................................................................................-0 5.5V Output Current (I ) ................................................................................................................................... 50 mA OUT Case Temperature Under ...
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SONET/SDH Clock Generator Package Pin Descriptions VCCT Page 8 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • ...
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Data Sheet VSC8121 Table 6: Package Pin Identification Signal Name Pin # CCT ...
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SONET/SDH Clock Generator Signal Name Pin # NOTE: (1) Leave unconnected. Terminating these pins to GND, VEE or otherwise may have an adverse effect on the performance of the ...
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Data Sheet VSC8121 Package Information TYP 10 o TYP K 0.30 RAD.TYP. 0.20 RAD. TYP . G52163-0, Rev 4.2 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 ...
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SONET/SDH Clock Generator Thermal Considerations This package has been enhanced with a copper heat slug to provide a low thermal resistance path from the die to the exposed surface of the heat spreader. The thermal resistance is shown in ...
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Data Sheet VSC8121 VSC8121 Evaluation Board An evaluation board is available from Vitesse which can be used to characterize the performance of the VSC8121 2.488GHz SONET/SDH Clock Generator. The following sections provide a layout for the board, general notes regarding ...
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SONET/SDH Clock Generator Figure 8: Location of Additional Components on Back Side of the VSC8121 Evaluation Board C6 Equipment for Typical Set-up VSC8121 Evaluation Board Signal Generator or 155.52MHz Crystal Oscillator Digital Oscilloscope DC Power Supply Power Supply Settings ...
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Data Sheet VSC8121 Table 10: REFSEL [0,1] Switch Settings (S1, S2) For Selected Reference Frequency REFSEL[0] (S1 reiterated above, the selected reference frequency is determined by the TTL inputs REFSEL[0] and REFSEL[1]. The board can be ...
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SONET/SDH Clock Generator Example Set-Up The figure below shows one possible set-up using the VSC8121 Evaluation Board and recommended con- nections listed above. In this configuration, the device receives its reference clock input from an external signal generator supplying ...
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Data Sheet VSC8121 Ordering Information The order number for this product is formed by a combination of the device number, and package type. Device Type 2.488GHz SONET/SDH Clock Generator Notice Vitesse Semiconductor Corporation (“Vitesse”) provides this document for informational purposes ...
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SONET/SDH Clock Generator Rev Item Date No. 1 4.1 2/4/00 General Description 2 4.1 2/4/00 3 4.1 2/4/00 4 4.1 2/4/00 5 4.1 2/4/00 6 4.1 2/4/00 7 4.1 2/4/00 8 4.1 2/4/00 Page 18 © VITESSE SEMICONDUCTOR CORPORATION ...