HD64F3644PV Datasheet, PDF (104/551 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 4 Clock Pulse Generators
4.2 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.
Connecting a Crystal Resonator: Figure 4.2 shows a typical method of connecting a crystal
resonator.
OSC ₁
OSC ₂
C₁
R_f
C₂
R _f = 1 MΩ ±20%
C₁ = C₂ = 12 pF ±20%
Figure 4.2 Typical Connection to Crystal Resonator
Figure 4.3 shows the equivalent circuit of a crystal resonator. An oscillator having the
characteristics given in table 4.1 should be used.
OSC₁
C_S
L_S
R_S
OSC₂
C₀
Figure 4.3 Equivalent Circuit of Crystal Resonator
Table 4.1 Crystal Resonator Parameters
Frequency
RS (max)
C0 (max)
2 MHz
500 Ω
7 pF
4 MHz
100 Ω
7 pF
8 MHz
50 Ω
7 pF
10 MHz
30 Ω
7 pF
Rev. 6.00 Sep 12, 2006 page 82 of 526
REJ09B0326-0600