 English |
|
|
|
|
|
|
|
| HD404449 Datasheet, PDF (41/123 Pages) Hitachi Semiconductor – HD404449 SERIES | |||
| |||
| ◁ |
Table 22 Oscillator Circuit Examples
External clock
operation
Circuit Configuration
External
oscillator
OSC 1
HD404449 Series
Circuit Constants
Open
OSC2
Ceramic oscillator
(OSC1, OSC2)
Crystal oscillator
(OSC1, OSC2)
C1
Ceramic
oscillator
OSC1
Rf
C2
GND
OSC2
C1
Crystal
oscillator Rf
OSC1
C2
GND
OSC2
L CS RS
Ceramic oscillator: CSA4.00MG (Murata)
Rf = 1 M⦠± 20%
C1 = C2 = 30 pF ± 20%
Rf = 1 M⦠± 20%
C1 = C2 = 10â22 pF ± 20%
Crystal: Equivalent to circuit shown below
C0 = 7 pF max
RS = 100 ⦠max
Crystal oscillator
(X1, X2)
OSC1
C0
C1
X1
Crystal
oscillator
C2
GND
X2
L CS RS
OSC2
Ceramic: 32.768 kHz: MX38T
(Nippon Denpa Kogyo)
C1 = C2 = 20 pF ± 20%
RS: 14 kâ¦
C0: 1.5 pF
X1
X2
C0
Notes: 1. Since the circuit constants change depending on the crystal or ceramic resonator and stray
capacitance of the board, the user should consult with the crystal or ceramic oscillator
manufacturer to determine the circuit parameters.
2. Wiring among OSC1, OSC2, X1, X2, and elements should be as short as possible, and must not
cross other wiring (see figure 27).
3. If the 32.768-kHz crystal oscillator is not used, the X1 pin must be fixed to GND and X2 must be
open.
41
|
▷ |
German
Russian
Spanish
Italian
Polish
Chinese
Japanese
Korean
French
Portuguese