HYB514256B Datasheet, PDF (8/22 Pages) Siemens Semiconductor Group – 256 K x 4-Bit Dynamic RAM Low Power 256 K x 4-Bit Dynamic RAM

HYB 514256B/BL/BJ/BJL-50/-60/-70
256 K × 4-DRAM
AC Characteristics (cont’d) ^{4) 13)}
T_A = 0 to 70 ˚C; V_CC = 5 V ± 10 %; t_T = 5 ns
Parameter
Symbol
-50
min. max.
Row address setup time
t_ASR
Row address hold time
t_RAH
Column address setup time t_ASC
Column address hold time t_CAH
Column address to RAS lead t_RAL
time
0–
10 –
0–
10 –
25 –
Read command setup time t_RCS
Read command hold time
t 8)
RCH
Read command hold time
t_RRH
referenced to RAS
8)
0–
0–
0–
Write command hold time
t_WCH
Write command pulse width t_WP
Write command to RAS lead t_RWL
time
10 –
10 –
15 –
Write command to CAS lead t_CWL
time
15 –
Data setup time
Data hold time
Refresh period
Refresh period
L-version
t 9)
DS
t 9)
DH
t_REF
t_REF
0–
10 –
–8
– 64
Write command setup time ¹⁰⁾ t_WCS
CAS to WE delay time
t 10)
CWD
RAS to WE delay time
t 10)
RWD
Column address to WE delay t_AWD
time
10)
0–
40 –
75 –
50 –
CAS setup time (CAS-before- t_CSR
RAS cycle)
5–
CAS hold time (CAS-before- t_CHR
RAS cycle)
10 –
RAS to CAS precharge time t_RPC
0–
Limit Values
-60
min. max.
0–
10 –
0–
15 –
30 –
-70
min. max.
0–
10 –
0–
15 –
35 –
0–
0–
0–
0–
0–
0–
10 –
10 –
15 –
15 –
15 –
20 –
15 –
20 –
0–
15 –
–8
– 64
0–
15 –
–8
––
0–
45 –
90 –
60 –
0–
50 –
100 –
65 –
5–
5–
15 –
15 –
0–
0–
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ms
ms
ns
ns
ns
ns
ns
ns
ns
Semiconductor Group
62