Exar Corporation XRK39351
The XRK39351 has an output/input frequency range of 25MHz to 200MHz with the PLL enabled and an input frequency range of 2MHz to 300MHz when the PLL is disabled (test mode). The XRK39351 has two reference clock inputs, one LVPECL and the other LVCMOS. The REF_SEL input selects clock input to be used as the PLL’s reference source.FEATURES
GENERAL DESCRIPTION
The XRK39351 is a low voltage PLL based clock driver designed for high speed clock distribution applications. The XRK39351 uses PLL technology to frequency lock its outputs to the clock reference input. The divider in the feedback path will determine the frequency of the VCO. The XRK39351 provides 9 LVCMOS outputs that are separated into 4 banks. Each of the separate output banks can individually divide down the VCO output frequency. This allows the XRK39351 to generate a variety of output-to-input frequency ratios (1:1, 1:2, 1:4, 2:1 and 4:1). All outputs provide LVCMOS compatible levels while driving 50Ω terminated transmission lines. The input reference clock can be directly applied to the output dividers bypassing the PLL when PLL_EN FIGURE 1. BLOCK DIAGRAM OF THE XRK39351 REF_SEL●
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● 9 LVCMOS Outputs (4 banks) 25 - 200 MHz output frequency range Fully Integrated PLL 2.5V or 3.3V Operation Selectable reference clock input, LVCMOS or LVPECL...