D12320VF25V Datasheet, PDF (647/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 17 ROM
17.11.4 Memory Read Mode
• After the end of an auto-program, auto-erase, or status read operation, the command wait state
is entered. To read memory contents, a transition must be made to memory read mode by
means of a command write before the read is executed.
• Command writes can be performed in memory read mode, just as in the command wait state.
• Once memory read mode has been entered, consecutive reads can be performed.
• After power-on, memory read mode is entered.
Table 17.16 AC Characteristics in Memory Read Mode
Conditions: V_CC = 3.3 V ±0.3 V, V_SS = 0 V, T_a = 25°C ±5°C
Item
Symbol
Min
Command write cycle
tnxtc
20
CE hold time
tceh
0
CE setup time
tces
0
Data hold time
tdh
50
Data setup time
tds
50
Write pulse width
twep
70
WE rise time
tr
—
WE fall time
tf
—
Max
Unit
—
μs
—
ns
—
ns
—
ns
—
ns
—
ns
30
ns
30
ns
A18 to A₀
Command write
Memory read mode
Address stable
CE
t_wep t_ceh
t_nxtc
OE
t_ces
WE
t_f
t_r
Data
H'00
t_dh
t_ds
Note: Data is latched at the rising edge of WE.
Data
Figure 17.22 Memory Read Mode Timing Waveforms after Command Write
Rev.7.00 Feb. 14, 2007 page 613 of 1108
REJ09B0089-0700