Section 18 Power-Down Mode
Rev. 1.00 Oct. 01, 2007 Page 684 of 1956
REJ09B0256-0100
18.8
RTC Power Supply Backup
18.8.1
Transition to RTC Power Supply Backup Mode
When entering the RTC power supply backup mode with the VDD power supply (1.2 V) turned
off, the VDD power supply should be turned off while the
XRTCSTBI
signal is held low. By
turning off the VDD power supply, the currents that might be generated in the VDD (1.2 V)
operating region can be eliminated to reduce power consumption. If the clock has been supplied
from the 32.768-Hz crystal, the RTC continues counting of its second to year counters while the
VDD (1.2 V) power supply is turned off.
18.8.2
Canceling RTC Power Supply Backup Mode
The RTC power supply backup mode is canceled by a power-on reset. Even when any interrupt
condition is satisfied in the RTC power supply backup mode, the interrupt-generating condition
will be canceled by the power-on reset. RTC power supply backup mode can be canceled in the
following steps.
1. Turn on the VDD power supply (1.2 V) while holding the
PRESET
signal low.
2. Since the VDD-RTC (3.3 V), which is exclusively used for the RTC, is supplied, drive the
XRTCSTBI
signal high only after the power-on oscillation stabilization time has elapsed after
the VDD (1.2 V) becomes stable. This is to prevent the LSI from being damaged by the
transient current.
3. Hold the
PRESET
signal low until the RTC is reset by the power-on reset, and then cancel the
power-on reset.
Table 18.5 shows the configuration of the pins related to RTC power supply backup mode.
Table 18.5 Pin Configuration
Pin Name
Function
I/O
Description
XRTCSTBI
RTC standby
Input
When this pin goes low, the LSI enters RTC
power supply backup mode.
Содержание SH7763
Страница 2: ...Rev 1 00 Oct 01 2007 Page ii of lxvi ...
Страница 122: ...Section 2 Programming Model Rev 1 00 Oct 01 2007 Page 56 of 1956 REJ09B0256 0100 ...
Страница 144: ...Section 3 Instruction Set Rev 1 00 Oct 01 2007 Page 78 of 1956 REJ09B0256 0100 ...
Страница 170: ...Section 4 Pipelining Rev 1 00 Oct 01 2007 Page 104 of 1956 REJ09B0256 0100 ...
Страница 282: ...Section 7 Caches Rev 1 00 Oct 01 2007 Page 216 of 1956 REJ09B0256 0100 ...
Страница 378: ...Section 9 Interrupt Controller INTC Rev 1 00 Oct 01 2007 Page 312 of 1956 REJ09B0256 0100 ...
Страница 514: ...Section 12 DDR SDRAM Interface DDRIF Rev 1 00 Oct 01 2007 Page 448 of 1956 REJ09B0256 0100 ...
Страница 630: ...Section 13 PCI Controller PCIC Rev 1 00 Oct 01 2007 Page 564 of 1956 REJ09B0256 0100 ...
Страница 686: ...Section 14 Direct Memory Access Controller DMAC Rev 1 00 Oct 01 2007 Page 620 of 1956 REJ09B0256 0100 ...
Страница 710: ...Section 16 Clock Pulse Generator CPG Rev 1 00 Oct 01 2007 Page 644 of 1956 REJ09B0256 0100 ...
Страница 732: ...Section 17 Watchdog Timer and Reset WDT Rev 1 00 Oct 01 2007 Page 666 of 1956 REJ09B0256 0100 ...
Страница 752: ...Section 18 Power Down Mode Rev 1 00 Oct 01 2007 Page 686 of 1956 REJ09B0256 0100 ...
Страница 772: ...Section 19 Timer Unit TMU Rev 1 00 Oct 01 2007 Page 706 of 1956 REJ09B0256 0100 ...
Страница 824: ...Section 21 Compare Match Timer CMT Rev 1 00 Oct 01 2007 Page 758 of 1956 REJ09B0256 0100 ...
Страница 1060: ...Section 23 Gigabit Ethernet Controller GETHER Rev 1 00 Oct 01 2007 Page 994 of 1956 REJ09B0256 0100 ...
Страница 1062: ...Section 24 IP Security Accelerator SECURITY Rev 1 00 Oct 01 2007 Page 996 of 1956 REJ09B0256 0100 ...
Страница 1124: ...Section 26 I 2 C Bus Interface IIC Rev 1 00 Oct 01 2007 Page 1058 of 1956 REJ09B0256 0100 ...
Страница 1184: ...Section 27 Serial Communication Interface with FIFO SCIF Rev 1 00 Oct 01 2007 Page 1118 of 1956 REJ09B0256 0100 ...
Страница 1350: ...Section 30 SIM Card Module SIM Rev 1 00 Oct 01 2007 Page 1284 of 1956 REJ09B0256 0100 ...
Страница 1484: ...Section 33 Audio Codec Interface HAC Rev 1 00 Oct 01 2007 Page 1418 of 1956 REJ09B0256 0100 ...
Страница 1560: ...Section 35 USB Host Controller USBH Rev 1 00 Oct 01 2007 Page 1494 of 1956 REJ09B0256 0100 ...
Страница 1720: ...Section 37 LCD Controller LCDC Rev 1 00 Oct 01 2007 Page 1654 of 1956 REJ09B0256 0100 ...
Страница 2025: ......
Страница 2026: ...SH7763 Hardware Manual ...