Information

PIC16C55X(A)
DS40143B/E1A-page 2  1998 Microchip Technology Inc.
TABLE 7-2: CAPACITOR SELECTION FOR CRYSTAL OSCILLATOR (PRELIMINARY)
Mode Freq OSC1(C1) OSC2(C2)
LP
32 kHz
200 kHz
68 - 100 pF
15 - 30 pF
68 - 100 pF
15 - 30 pF
XT
100 kHz
2 MHz
4 MHz
68 - 150 pF
15 - 30 pF
15 - 30 pF
150 - 200 pF
15 - 30 pF
15 - 30 pF
HS
8 MHz
10 MHz
20 MHz
15 - 30 pF
15 - 30 pF
15 - 30 pF
15 - 30 pF
15 - 30 pF
15 - 30 pF
Higher capacitance increases the stability of the oscillator but also increases the start-up time. These values are for design guidance
only. Rs may be required in HS mode as well as XT mode to avoid overdriving crystals with low drive level specification. Since each
crystal has its own characteristics, the user should consult the crystal manufacturer for appropriate values of external components.
Crystals to be Characterized:
32.768 kHz Epson C-001R32.768K-A ± 20 PPM
100 kHz Epson C-2 100.00 KC-P ± 20 PPM
200 kHz STD XTL 200.000 kHz ± 20 PPM
4.0 MHz ECS ECS-40-20-4 ± 50 PPM
20.0 MHz ECS ECS-200-20-4 ± 50 PPM