Table of Contents
Advertisement
9.3
Oscillator
Clock pulses can be supplied by connecting a crystal resonator, or by input of an external clock.
9.3.1
Connecting a Crystal Resonator
Circuit Configuration: A crystal resonator can be connected as shown in the example in figure
9.2. An AT-cut parallel-resonance crystal should be used.
Crystal Resonator: Figure 9.3 shows the equivalent circuit of the crystal resonator. Use a crystal
resonator that has the characteristics shown in table 9.2 and the same frequency as the system
clock (φ).
Table 9.2
Crystal Resonator Parameters
Frequency (MHz)
R
max (Ω)
S
C
max (pF)
O
Rev. 1.0, 02/00, page 176 of 1141
OSC1
OSC2
Figure 9.2 Connection of Crystal Resonator (Example)
L
OSC1
Figure 9.3 Crystal Resonator Equivalent Circuit
C
L1
C
C
L1 =
C
L2
C
L
R
s
AT-cut parallel-resonance type
C
0
8
80
7
= 10 to 22pF
L2
OSC2
10
60
7
Advertisement
Table of Contents
