SH7047 Datasheet, PDF (656/764 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTMRISC engine Family/SH7000 Series

24.4.2 Current Consumption during Oscillation Stabilization Wait Period
Current consumption increases during the oscillation stabilization wait period.
24.4.3 On-Chip Peripheral Module Interrupt
Relevant interrupt operations cannot be performed in module standby mode. Consequently, if the
CPU enters module standby mode while an interrupt has been requested, it will not be possible to
clear the CPU interrupt source or the DTC activation source.
Interrupts should therefore be disabled before entering module standby mode.
24.4.4 Writing to MSTCR1 and MSTCR2
MSTCR1 and MSTCR2 should only be written to by the CPU.
24.4.5 Handling of HSTBY Pin
Power should not be supplied while the HSTBY pin is at the low level. To enter hardware standby
mode, the HSTBY pin can be set to the low level when the oscillation stabilization time has
elapsed after power supply.
24.4.6 Electromagnetic Interference on HSTBY Pin
The HSTBY signal controls start and stop for all functions of this LSI, including the clock pulse
generator. Therefore, please keep in mind that electromagnetic interference on the HSTBY pin
causes malfunction of this LSI.
If using the hardware standby function of this LSI which is exposed to the environment in which
lots of electromagnetic interference sources exist, connecting a noise filter such as an R-C circuit
shown in figure 24.4 to the HSTBY pin is recommended.
HSTBY
control curcuit
R
C
HSTBY
This LSI
C: 0.1µF
R: 10k to 100k Ω (recommendation)
Figure 24.4 Example of External Circuit Connected to HSTBY Pin
Rev. 2.00, 09/04, page 616 of 720