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External circuitry such as that shown below is recommended around the PLL.
R1: 3 kΩ
C1: 470 pF
PLLCAP
Rp: 200 Ω
PLLVCC
CPB: 0.1 µF *
PLLVSS
PVCC
VCC
CB: 0.1 µF *
CB: 0.1 µF *
VSS
(Values are recommended values.)
Note: * CB and CPB are laminated ceramic capacitors.
Figure 23-5 Points for Attention when Using PLL Oscillation Circuit
Place oscillation stabilization capacitor C1 and resistor R1 close to the PLLCAP pin, and ensure
that no other signal lines cross this line. Supply the C1 ground from PLLVSS.
Separate PLLVCC and PLLVSS from the other VCC and VSS lines at the board power supply
source, and be sure to insert bypass capacitors CPB and CB close to the pins.
846
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