HD6432670 Hitachi, HD6432670 Datasheet - Page 264

• Manufacturer Part Number: HD6432670
• Description: (HD64F267x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

T
T
T
Software standby
Rp
Rr
Rc2
SDRAMø
Address bus
Precharge-sel
CKE
PALL
SELF
NOP
Figure 6.57 Self-Refresh Timing
(TPC1 = 1, TPC0 = 0, RCW1 = 0, RCW0 = 0, RLW1 = 0, RLW0 = 0)
In some synchronous DRAMs provided with a self-refresh mode, the interval between clearing
self-refreshing and the next command is specified. A setting can be made in bits TPCS2 to TPCS0
in REFCR to make the precharge time after self-refreshing from 1 to 7 states longer than the
normal precharge time. In this case, too, normal precharging is performed according to the setting
of bits TPC1 and TPC0 in DRACCR, and therefore a setting should be made to give the optimum
post-self-refresh precharge time, including this time. Figure 6.58 shows an example of the timing
when the precharge time after self-refreshing is extended by 2 states.
Rev. 2.0, 04/02, page 218 of 906