HD6473847RHV Datasheet, PDF (136/546 Pages) Renesas Technology Corp – Renesas 8-Bit Single-Chip Microcomputer H8 Family / H8/300L Super Low Power Series

Section 4 Clock Pulse Generators
PB3
X1
X2
Vss
OSC2
OSC1
TEST
(Vss)
Figure 4.13 Example of Crystal and Ceramic Resonator Arrangement
Figure 4.14 (1) shows an example of the measurement circuit for the negative resistor which is
recommended by the resonator manufacturer. Note that if the negative resistor in this circuit does
not reach the level which is recommended by the resonator manufacturer, the main oscillator may
be hard to start oscillation.
If the negative resistor does not reach the level which is recommended by the resonator
manufacturer and oscillation is not started, changes as shown in figure 4.14 (2) to (4) should be
made. The proposed change and capacitor size to be applied should be determined according to the
evaluation result of the negative resistor and frequency deviation, etc.
Rev. 7.00 Mar. 08, 2010 Page 104 of 510
REJ09B0024-0700