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VDD-RTC
Noise filter
R
RTC
3.3 V
Notes: 1. Select either the C
requirements such as the adjustment range, degree of stability, etc.
2. Built-in resistance value R
3. C
and C
in
out
earth board.
4. The crystal oscillation stabilization time depends on the mounted circuit constants, floating
capacitance, etc., and should be decided after consultation with the crystal resonator
manufacturer.
5. Place the crystal resonator and load capacitors C
(Correct oscillation may not be possible if there is externally induced noise in the EXTAL2 and
XTAL2 pins.)
6. Ensure that the crystal resonator connection pin (EXTAL2 and XTAL2) wiring is routed as far away
as possible from other power lines (except GND) and signal lines.
7. Insert a noise filter in the RTC power supply.
The values of C
Figure 11.5 Example of Crystal Oscillator Circuit Connection
VSS-RTC
C
RTC
or C
side for the frequency adjustment variable capacitor according to
in
out
(typ. value) = 10 MΩ, R
f
values include floating capacitance due to the wiring. Take care when using a solid-
and R
depend on the bus and CPU frequency.
RTC
RTC
SH7750
Series
EXTAL2
C
in
(typ. value) = 400 kΩ
D
and C
as close as possible to the chip.
in
out
Rev. 4.0, 04/00, page 239 of 850
R
f
R
D
XTAL2
XTAL
C
out
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