TMS416409A, TMS417409A, TMS426409A, TMS427409A
4194304 BY 4-BIT EXTENDED DATA OUT
DYNAMIC RANDOM-ACCESS MEMORIES
SMKS893B – AUGUST 1996 – REVISED APRIL 1997
15
POST OFFICE BOX 1443 • HOUSTON, TEXAS 77251–1443
timing requirements over recommended ranges of supply voltage and operating free-air
temperature (see Note 4)
’41x409A-50
’42x409A-50
’41x409A-60
’42x409A-60
’41x409A-70
’42x409A-70
UNIT
MIN MAX MIN MAX MIN MAX
t
RC
Cycle time, random read or write 84 104 124 ns
t
RWC
Cycle time, read-write 111 135 160 ns
t
RASP
Pulse duration, RAS active, fast page mode (see Note 8) 50 100000 60 100 000 70 100000 ns
t
RAS
Pulse duration, RAS active, non-page mode (see Note 8) 50 10 000 60 10 000 70 10 000 ns
t
RP
Pulse duration, RAS precharge 30 40 50 ns
t
WP
Pulse duration, write command 8 10 10 ns
t
ASC
Setup time, column address 0 0 0 ns
t
ASR
Setup time, row address 0 0 0 ns
t
DS
Setup time, data in (see Note 9) 0 0 0 ns
t
RCS
Setup time, read command 0 0 0 ns
t
CWL
Setup time, write command before CAS precharge 8 10 12 ns
t
RWL
Setup time, write command before RAS precharge 8 10 12 ns
t
WCS
Setup time, write command before CAS active
(early-write only)
0 0 0 ns
t
WRP
Setup time, W high before RAS low (CBR refresh only) 10 10 10 ns
t
WTS
Setup time, W low before RAS low (test mode only) 10 10 10 ns
t
CSR
Setup time, CAS referenced to RAS (CBR refresh only) 5 5 5 ns
t
CAH
Hold time, column address 8 10 12 ns
t
DH
Hold time, data in (see Note 9) 8 10 12 ns
t
RAH
Hold time, row address 8 10 10 ns
t
RCH
Hold time, read command referenced to CAS (see Note 10) 0 0 0 ns
t
RRH
Hold time, read command referenced to RAS (see Note 10) 0 0 0 ns
t
WCH
Hold time, write command during CAS active
(early-write only)
8 10 12 ns
t
ROH
Hold time, RAS referenced to OE 8 10 10 ns
t
WRH
Hold time, W high after RAS low (CBR refresh) 10 10 10 ns
t
WTH
Hold time, W low after RAS low (test mode only) 10 10 10 ns
t
CHR
Hold time, CAS referenced to RAS (CBR refresh only) 10 10 10 ns
t
OEH
Hold time, OE command 13 15 18 ns
t
RHCP
Hold time, RAS active from CAS precharge 28 35 40 ns
NOTES: 4. With ac parameters, it is assumed that tT = 2 ns.
8. In a read-write cycle, t
RWD
and t
RWL
must be observed.
9. Referenced to the later of CAS
or W in write operations
10. Either t
RRH
or t
RCH
must be satisfied for a read cycle.