HD6417320 RENESAS [Renesas Technology Corp], HD6417320 Datasheet - Page 646

• Manufacturer Part Number: HD6417320
• Description: Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 17 Realtime Clock (RTC)
17.5.4
Crystal oscillator circuit constants (recommended values) are shown in table 17.2, and the RTC
crystal oscillator circuit in figure 17.5.
Table 17.2 Recommended Oscillator Circuit Constants (Recommended Values)
Rev. 3.00 Jan. 18, 2008 Page 584 of 1458
REJ09B0033-0300
f
32.768 kHz
osc
Notes: 1. Select either the C
Crystal Oscillator Circuit
This LSI
2. Built-in resistance value R
3. C
4. The crystal oscillation settling time depends on the mounted circuit constants,
5. Place the crystal resonator and load capacitors C
6. Ensure that the crystal resonator connection pin (EXTAL_RTC, XTAL_RTC)
according to requirements such as frequency range, degree of stability, etc.
when using a ground plane.
stray capacitance, etc., and should be decided after consultation with the crystal
resonator manufacturer.
to the chip.
(Correct oscillation may not be possible if there is externally induced noise in the
EXTAL_RTC and XTAL_RTC pins.)
wiring is routed as far away as possible from other power lines (except GND) and
signal lines.
in
Figure 17.6 Example of Crystal Oscillator Circuit Connection
and C
out
values include floating capacitance due to the wiring. Take care
EXTAL_RTC
C
in
in
C
10 to 22 pF
or C
in
out
R
f
f
(Typ value) = 10 MΩ, R
side for frequency adjustment variable capacitor
XTAL
XTAL_RTC
R
D
C
out
in
D
and C
C
10 to 22 pF
(Typ value) = 400 kΩ
out
out
as close as possible