NV021AMLF datasheet(6/15 Pages) RENESAS

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NV021 Data Sheet

Revision B January 26, 2016

APPLICATION INFORMATION

Figure 2. CRYSTAL INPUt INTERFACE

CRYSTAL INPUT INTERFACE

The NV021 has been characterized with 18pF parallel

resonant crystals. The capacitor values, C1 and C2, shown in

Figure 2 below were determined using a 25MHz, 18pF parallel

resonant crystal and were chosen to minimize the ppm error.

The optimum C1 and C2 values can be slightly adjusted for

different board layouts.

POWER SUPPLY FILTERING TECHNIQUES

As in any high speed analog circuitry, the power supply

pins are vulnerable to random noise. The NV021 provides

separate power supplies to isolate any high switching

noise from the outputs to the internal PLL. V

CC and VCCA

should be individually connected to the power supply

plane through vias, and bypass capacitors should be

used for each pin. To achieve optimum jitter performance,

power supply isolation is required. Figure 1 illustrates how

a 10

Ω resistor along with a 10μF and a .01μF bypass

capacitor should be connected to each V

CCA pin.

FIGURE 1. POWER SUPPLY FILTERING

CCA

μF

.01

μF

3.3V

.01

μF

NV021AMLF Fiches technique(PDF) 6 Page - Renesas Technology Corp