AM29F002BT-70JC Spansion Inc., AM29F002BT-70JC Datasheet - Page 22

• Manufacturer Part Number: AM29F002BT-70JC
• Description: Flash Memory IC
• Manufacturer: Spansion Inc.

Specifications of AM29F002BT-70JC

• Memory Size: 2Mbit
• Memory Configuration: 256K X 8
• Ic Interface Type: Parallel
• Access Time: 70ns
• Memory Case Style: PLCC
• No. Of Pins: 32
• Operating Temperature Range: 0°C To +70°C
• Termination Type: SMD

T h e D Q 5 fai lur e c o nd itio n c a n ap p ea r if th e s y s te m
trie s to pro gra m a “1 ” to a l oc ation that is pr ev iou sl y p ro-
gr am m ed to “ 0.” O nly an er a se op e r atio n ca n ch an g e
a “ 0” b a ck to a “ 1 .” U n de r thi s c on dition , the dev ic e
h a l ts th e o p e ra ti o n , a n d w h e n t h e o p e r a tio n h a s
ex c ee ded th e ti m ing li m its, D Q5 p rod uc es a “1 .”
U n der both th es e c on ditio ns , the s y ste m m us t is su e the
re s et c om m a nd to re tur n th e dev i c e to r ead in g arr ay
d ata.
DQ3: Sector Erase Timer
A fte r w ritin g a s e c tor era s e c om m a nd s e qu en c e, the
s y s te m c an rea d D Q 3 to d eter m ine w he th er or n ot an
e ras e op era tio n ha s b eg un . ( T he s e c tor e ra s e ti m er
d oe s n ot a pp ly to th e c hip e ra s e c om m an d.) If ad di -
tion al s ec tor s a re s ele c te d fo r era su re, the en tire tim e-
o ut als o app lies a fter ea ch ad dition al s e c to r era s e c om -
m a nd . W he n th e tim e- out is c o m ple te , D Q 3 s w itc he s
fr o m “0 ” to “ 1.” T h e s y s te m c a n i g n or e D Q 3 i f t he
s y s te m c an g uar antee tha t th e tim e b etw een a ddi tio na l
s ec tor era se c om m a nd s is les s than 50
E ras e C om m and S eq uen c e”
A fter the s ec tor e ras e c om m a nd s eq ue nc e is w r itte n,
th e s y s tem s ho u ld re a d th e s ta tu s o n D Q 7 ( D a ta#
Po lling ) or D Q 6 (To ggle Bit I) to ens u re the d ev ic e ha s
a cc e pted th e c o m m an d s eq ue nc e, an d the n r ead D Q 3.
If D Q3 is “1 ”, the inter na lly c on tr olle d e ras e c yc le ha s
b eg un ; al l fu rthe r c om m and s ( othe r than E ra s e Su s -
p end ) ar e ig nor ed until th e er as e o per ation is c om p lete.
If D Q3 is “0” , th e de vi ce ac c ep ts a dd iti ona l s ec tor eras e
c o m m a n d s . T o e n s u r e th e c o m m a n d h a s b e e n
a cc e pted, th e s y s tem so ftw ar e s h oul d c h ec k the s ta tu s
o f D Q 3 pri or to an d follow i ng eac h s ub se qu ent s e ctor
e ras e c om m a nd. If D Q 3 is h igh on the s ec o nd s ta tu s
c h e c k , t h e l a s t c o m m a n d m i g h t n o t h a v e b e e n
a cc e pted.
2 0
Table 6
sh ow s th e ou tp uts for D Q3 .
on pag e 14.
µ
s. S ee
A m 29 F 002 B /A m 29 F 00 2N B
“ Se ctor
Notes:
1. Read toggle bit twice to determine whether or not it is
2. Recheck toggle bit because it can stop toggling as DQ5
toggling. See text.
changes to “1”. See text.
No
F igu r e 5 .
Complete, Write
Reset Command
Read DQ7–DQ0
Read DQ7–DQ0
Read DQ7–DQ0
Program/Erase
Operation Not
Toggle Bit
Toggle Bit
= Toggle?
DQ5 = 1?
= Toggle?
START
Twice
Yes
Yes
Yes
To g g le B it A lg o r ith m
(N otes
1, 2)
(N ote
Operation Complete
No
No
Program/Erase
1)