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Spw-10x spacewire router – Atmel SpaceWire Router SpW-10X User Manual

Page 46

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Ref.: UoD_SpW-10X_

UserManual

Issue: 3.4

SpW-10X

SpaceWire Router

User Manual

Date: 11

th

July 2008

Preliminary

46

Figure 5-3 PLL with external components

The PLL loop filter component values to be used are

R = 10 k

Ω

C = 120 pF

C0 = 3.3 pf.

The VCO bias resistor depends on the required VCO frequency range which is determined by the PLL
feedback divider (NF in Figure 5-3). The VCO bias resistor values to use are

Rvco = 4.7 k

Ω for 100-150MHz (FEEDBDIV = 0b000, 0b001, or 0b010),

Rvco = 1.8 k

Ω for 150MHz-200MHz (FEEDBDIV = 0b011, 0b100, 0b101 or 0b110, or 0b111).

See section 5.1 for information about the FEEDBDIV inputs.

A dedicated decoupling capacitors (100 nF and 1µF) are required for the PLL power supply.