Section 18 Power-Down Mode
Rev. 1.00 Oct. 01, 2007 Page 682 of 1956
REJ09B0256-0100
Transition to self-refresh
mode completed
System power
supply
turned off
System power
supply
turned on
Power-on
reset
canceled
M_CKE asserted
by SMS bits in SCR
Delay time of
LSI internal reset
PRESET
DDRIF reset
VDD
(1.2 V, 3.3 V)
M_CKE
M_BKPRST
Figure 18.1 DDR-SDRAM Interface Operation when
Turning System Power Supply On/Off
18.7.2
DDR-SDRAM Backup Sequence when Turning Off System Power Supply
The sequence when the system power supply is turned off is shown below.
Figure 18.2 shows the sequence of entering the self-refresh mode and turning off the system
power supply.
1. Confirm that all transactions of the DDRIF caused by on-chip peripheral modules are
completed.
2. Issue the all bank precharge command (PREALL) with bits SMS2 to SMS0 in SCR by
software. Activated banks will be closed. After that, issue the auto-refresh command (REFA)
with bits SMS2 to SMS0 in SCR to perform CBR refresh on all rows.
3. Specify the DRE and RMODE bits in the MIM register of the DDRIF to put the SDRAM into
the self-refresh mode. At this time, keep the DCE bit set to 1. The DDRIF automatically issues
a self-refresh command and drives the M_CKE signal low. After that, the DDR-SDRAM will
automatically enter the power-down mode.
4. The SELFS bit in MIM is set to 1.
5. Drive the
M_BKPRST
pin from high to low.
The M_CKE output will be unstable immediately after the system power supply is turned off.
Therefore, before turning off the system power supply, use the
M_BKPRST
signal, which is a
signal outside the LSI, to keep the M_CKE signal input of the DDR-SDRAM low until the
power-on reset is canceled (figure 18.1).
6. Turn off the system power supply (1.2 V and 3.3 V).
Summary of Contents for SH7763
Page 2: ...Rev 1 00 Oct 01 2007 Page ii of lxvi ...
Page 122: ...Section 2 Programming Model Rev 1 00 Oct 01 2007 Page 56 of 1956 REJ09B0256 0100 ...
Page 144: ...Section 3 Instruction Set Rev 1 00 Oct 01 2007 Page 78 of 1956 REJ09B0256 0100 ...
Page 170: ...Section 4 Pipelining Rev 1 00 Oct 01 2007 Page 104 of 1956 REJ09B0256 0100 ...
Page 282: ...Section 7 Caches Rev 1 00 Oct 01 2007 Page 216 of 1956 REJ09B0256 0100 ...
Page 378: ...Section 9 Interrupt Controller INTC Rev 1 00 Oct 01 2007 Page 312 of 1956 REJ09B0256 0100 ...
Page 514: ...Section 12 DDR SDRAM Interface DDRIF Rev 1 00 Oct 01 2007 Page 448 of 1956 REJ09B0256 0100 ...
Page 630: ...Section 13 PCI Controller PCIC Rev 1 00 Oct 01 2007 Page 564 of 1956 REJ09B0256 0100 ...
Page 710: ...Section 16 Clock Pulse Generator CPG Rev 1 00 Oct 01 2007 Page 644 of 1956 REJ09B0256 0100 ...
Page 732: ...Section 17 Watchdog Timer and Reset WDT Rev 1 00 Oct 01 2007 Page 666 of 1956 REJ09B0256 0100 ...
Page 752: ...Section 18 Power Down Mode Rev 1 00 Oct 01 2007 Page 686 of 1956 REJ09B0256 0100 ...
Page 772: ...Section 19 Timer Unit TMU Rev 1 00 Oct 01 2007 Page 706 of 1956 REJ09B0256 0100 ...
Page 824: ...Section 21 Compare Match Timer CMT Rev 1 00 Oct 01 2007 Page 758 of 1956 REJ09B0256 0100 ...
Page 1124: ...Section 26 I 2 C Bus Interface IIC Rev 1 00 Oct 01 2007 Page 1058 of 1956 REJ09B0256 0100 ...
Page 1350: ...Section 30 SIM Card Module SIM Rev 1 00 Oct 01 2007 Page 1284 of 1956 REJ09B0256 0100 ...
Page 1484: ...Section 33 Audio Codec Interface HAC Rev 1 00 Oct 01 2007 Page 1418 of 1956 REJ09B0256 0100 ...
Page 1560: ...Section 35 USB Host Controller USBH Rev 1 00 Oct 01 2007 Page 1494 of 1956 REJ09B0256 0100 ...
Page 1720: ...Section 37 LCD Controller LCDC Rev 1 00 Oct 01 2007 Page 1654 of 1956 REJ09B0256 0100 ...
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Page 2026: ...SH7763 Hardware Manual ...