SH7763 Datasheet, PDF (848/2026 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC Engine Family SH-4A Series

Section 22 Realtime Clock (RTC)
VDD-RTC
Noise filter
R RTC
3.3 V
C RTC
This LSI
VSS-RTC
Rf
EXTAL2
XTAL
C in
RD
XTAL2
C out
Notes: 1. Select either the C_in or C_out side for the frequency adjustment variable capacitor according to requirements
such as the adjustment range, degree of stability, etc.
2. Built-in resistance value R_f (typ. value) = 10 MΩ, R_D (typ. value) = 400 kΩ
3. C_in and C_out values include floating capacitance due to the wiring. Take care when using a solidearth 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_in and C_out as close as possible to the chip.
(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.
Figure 22.5 Example of Crystal Oscillator Circuit Connection
22.7.3 Interrupt source and request generating order
If it occurs two or three interrupt source of alarm interrupts(ATI), periodic interrupts(PFI), and
carry interrupts(CUI) at the same time, RTC generates interrupt request as the order of table 22.5.
Table 22.5 Interrupt source and request generating order
Interrupt source
Interrupt request generating order
Fast
ATI, PFI and CUI PFI
CUI
ATI
ATI and PFI
PFI
ATI
—
PFI and CUI
PFI
CUI
—
ATI and CUI
CUI
ATI
—
Rev. 1.00 Oct. 01, 2007 Page 782 of 1956
REJ09B0256-0100