Microsemi ZLE30267, Руководство по оборудованию

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ZLE30267 Hardware Guide
December 2015 25
Figure 10 · ZLE30267 Oscillator / Crystal Daughter Card Schematic
The assembly drawing for the ZLE30267 oscillator / crystal daughter card is shown in Figure 11 . The
physical layout of the card layout is similar to the schematic with connector JP1 located in the center of the
board, all oscillator circuit components located on the left side of JP1, and all crystal resonator circuit
components located on the right side of JP1. When an XO or crystal daughter card assembly is built, only
one of these two circuits is populated.
Figure 11 · ZLE30267 Oscillator / Crystal Daughter Assembly Drawing
Oscillator Daughter Card Assembly
The ZLE30267 oscillator / crystal daughter is provided with components JP1, C2, and R2 pre-installed. An
oscillator daughter card assembly is built by installing two additional components. The first component is the
oscillator to be evaluated which is installed at site Y1 or Y3 based on its package size. The second
component is resistor R3 which is the series source termination resistor for the oscillator output clock signal.
The value of R3 is chosen such the total impedance of the oscillator output driver and R3 is 50
Ω. An
example of an oscillator daughter card assembly is shown in Figure12 . The installed components are
indicated in red.
Figure 12 · ZLE30267 Oscillator / Crystal Daughter Assembly Drawing