HD64F3664FPV Datasheet, PDF (108/446 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 5 Clock Pulse Generators
5.1 System Clock Generator
Clock pulses can be supplied to the system clock divider either by connecting a crystal or ceramic
resonator, or by providing external clock input. Figure 5.2 shows a block diagram of the system
clock generator.
OSC ₂
OSC ₁
LPM
LPM: Low-power mode (standby mode, subactive mode, subsleep mode)
Figure 5.2 Block Diagram of System Clock Generator
5.1.1 Connecting Crystal Resonator
Figure 5.3 shows a typical method of connecting a crystal resonator. An AT-cut parallel-resonance
crystal resonator should be used. Figure 5.4 shows the equivalent circuit of a crystal resonator. A
resonator having the characteristics given in table 5.1 should be used.
OSC ₁
OSC ₂
C₁
C₂
C₁ = C₂ = 12 pF ±20%
Note: Capacitances are reference values.
Figure 5.3 Typical Connection to Crystal Resonator
OSC₁
L_S
C_S
R_S
C₀
OSC₂
Figure 5.4 Equivalent Circuit of Crystal Resonator
Rev. 6.00 Mar. 24, 2006 Page 78 of 412
REJ09B0142-0600