Datasheet

Table Of Contents
Section 5 Clock Pulse Generator
Rev. 2.00 Jul. 04, 2007 Page 96 of 692
REJ09B0309-0200
Figure 5.10 (1) shows an example measuring circuit with the negative resistance recommended by
the resonator manufacturer. Note that if the negative resistance of the circuit is less than that
recommended by the resonator manufacturer, it may be difficult to start the main oscillator.
If it is determined that oscillation does not occur because the negative resistance is lower than the
level recommended by the resonator manufacturer, the circuit must be modified as shown in figure
5.10 (2) through (4). Which of the modification suggestions to use and the capacitor capacitance
should be decided based upon evaluation results such as the negative resistance and the frequency
deviation.
(1) Negative Resistance Measuring Circuit
(2) Oscillator Circuit Modification Suggestion 1
(3) Oscillator Circuit Modification Suggestion 2
(4) Oscillator Circuit Modification Suggestion 3
C
3
OSC1
OSC2
C
1
C
2
Negative resistance,
addition of -R
OSC1
OSC2
C
1
C
2
Modification
point
Modification
point
Modification
point
OSC1
OSC2
C
1
C
2
OSC1
OSC2
C
1
C
2
Figure 5.10 Negative Resistance Measurement and Circuit Modification Suggestions