HD6433802H Datasheet, PDF (105/435 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

4.3 Subclock Generator
1. Connecting a 32.768 kHz/38.4 kHz crystal oscillator
Clock pulses can be supplied to the subclock divider by connecting a 32.768 kHz/38.4 kHz crystal
oscillator, as shown in figure 4.7. Follow the same precautions as noted under 3. notes on board
design for the system clock in 4.2.
X₁
C₁
C₁ = C ₂ = 15 pF (typ.)
Frequency Crystal oscillator
Products Name
X₂
32.768 kHz Nihon Denpa Kogyo MX73P
C₂
38.4 kHz Seiko Instrument Inc. VTC-200
Figure 4.7 Typical Connection to 32.768 kHz/38.4 kHz Crystal Oscillator (Subclock)
Figure 4.8 shows the equivalent circuit of the 32.768 kHz/38.4 kHz crystal oscillator.
C_S
L_S
X₁
R_S
X₂
C₀
C₀ = 1.5 pF typ
R_S = 14 kΩ typ
f _W = 32.768 kHz/38.4kHz
Figure 4.8 Equivalent Circuit of 32.768 kHz/38.4 kHz Crystal Oscillator
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